comments by john fenn on some of his publications1 · 2011-11-23 · comments by john fenn on some...
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Comments by John Fenn on Some of his Publications1
What follows is a collection of reflections and personal feelings about some of the papers from
studies that my many colleagues and I have published over the past half century. The number
beginning each paragraph refers to the paper with that number in my accompanying Curriculum
Vita. 2
The comments are necessarily subjective so that any suggestions on the “value” of a
paper are probably not an objective measure of its real worth. The author of a plurality of
papers is like a parent with many children who sees something special in each one of them!
5 & 6 shows the design of, and early results obtained with the original molecular beam system,
assembled and operated at Princeton beginning about 1958. Perhaps the most important
revelation was in #6. We had discovered a then little known research memorandum by Owen
and Thornhill of the Royal Aircraft Establishment in the UK giving the results of solutions of
Euler’s equation (by the method of characteristics) for the Mach number distribution along the
axis of a free jet from a sonic orifice exhausting into vacuum. We showed that these solutions
applied to the free jets from our tiny nozzles and that they represented a framework for
understanding and interpreting observations on the properties of molecules in those jets and the
beams extracted from them. Later papers by Ashkenas and Sherman along with book chapters
by Jim Anderson and Dave Miller extended those calculations and provided a more complete
map of the structure and properties of such jets and the states of their molecules. The early and
only marginally successful experiments by Kistiakowsky and Schlicter, and the subsequent and
more successful experiments by E.W. Becker and his colleagues in Germany, had been with
small converging-diverging nozzles as prescribed by Kantrowitz and Grey. Viscous boundary
layer effects in the diverging sections of such nozzles destroyed the isentropicity of the flow so
that the experimental results were disappointing. Becker’s group found empirically that more
intense beams were obtained when the diverging sections were removed but they initially did
not understand what went on in the resulting free jet expansions. They even assumed that Mach
Number decreased with the increasing distance along the jet axis! After these initial
misunderstandings had been sorted out, the descriptions of free jet expansions based on MOC
solutions of the flow equations, first by Owen and Thornhill and subsequently and more
completely by others, have provided a foundation for many studies of and with free jet
expansions including the experimental determinations of relaxation rates and terminal states for
internal molecular energy as well as the kinetics of cluster formation.
1 These remarks were prepared by John B. Fenn to help his colleague Gary Haller respond to the Swedish Academy
of Sciences request for nominations for the 2002 Chemistry Nobel Price. The text is of considerable scientific and
historical interest, and is therefore made public here with minimal edits. All the footnotes are from the editors
(Rosner, Haller, Gomez and Fernandez de la Mora). The original text is preserved in Professor Haller’s archives.
2 The attached CV is copied from Fenn’s original.
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8. The experiments of Vic Reis (my first graduate student) described in this paper showed that
the strong separation of heavy and light species, first found by Becker and then reproduced by
others, were not due to differences in radial diffusion rates in the free jet for heavy and light
species, as proposed by Becker and assumed to be true by all his followers. Instead they were
due to inertial effects in the stagnation of supersonic gas on small probes. Such inertial
separation had long been known for the case of relatively massive aerosol particles in air and
other gases. Moreover, by measuring the dependence of particles collection rate on target
diameter investigators had been able to determine particle size distributions of particulate matter
in gases. However, nobody had found or anticipated that such inertial separation could occur
with molecules. It is interesting that for a long time after we published this paper Becker
continued to insist that diffusion was the governing mechanism. He exploited this erroneous
assumption to the tune of millions of Deutschmarks to finance a large R&D program for
uranium enrichment which culminated in the construction of a demonstration plant for Brazil.
Gradually, over the years, he began to refer to “inertial separation” as the basis for the
enrichment but I don’t think he ever forgave us for discovering his error. His jet inertial
enrichment process worked and had some advantages over gaseous diffusion but the program
faded away after the bottom dropped out of the market for enriched uranium. Moreover, the gas
centrifuge and the laser processes proved far superior. Even so Becker’s large institute at the
German Kernforschungzentrum near Karlsruhe still survives and is engaged in various other
high tech projects. Becker himself recently retired. Also surviving is another application of the
“trennduse” (separating Nozzle) which was developed in a cooperation between Becker and a
Swedish chromatographer, Ryhage. The result was the “jet separator” which has been, and still
is, widely used to concentrate the analyze species in the fraction of effluent from a gas
chromatograph that is fed into a mass spectrometer. To this day the official description of terms
published by the ASMS says that the jet separator is a device that depends upon diffusion to
enrich the analyte concentration in carrier gas from a GC that is fed into a mass spectrometer!
Meanwhile, Juan de la Mora and his colleagues have developed rigorous kinetic and gas
dynamic theory describing inertial separation of heavy and light gaseous species. In addition
they have studied the phenomenon experimentally and developed methods for aerodynamic
sizing of aerosol particles including those too small to be seen by optical means.
9, 26 & 30 cover the work of graduate students George Maise and John Chang. George built a
novel probe for measuring the adiabatic recovery factor that characterizes the temperature
reached by rarefied gas when it is brought to rest from high velocity. The experiments showed
that such factors for mixtures of light and heavy species were anomalously high, seemingly in
violation of energy conservation. In fact the high stagnation temperature is a direct
consequence of the enrichment of heavy species in the stagnation zone of the probe. The heavy
molecules have a higher translation energy than light molecules travelling at the same velocity.
When that energy is thermalized by stagnation the temperature of the heavy molecules is higher
than that of the light molecules. Because the heavy molecules are at higher concentration in the
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stagnation zone than are the light molecules, the measured temperature in that zone is perforce
higher than it would be for a gas of uniform composition. John Chang made extensive direct
studies of these separation effects and was able to construct a two-fluid model of the stagnation
process that accounted for and correlated the enrichment and recovery factor observations.
10 & 11. These two review papers became a “handbook” for people entering the free jet beam
business. They were probably the most frequently cited of our publications until the advent of
electrospray.
12. demonstrated quantitatively the remarkably low temperatures that could be reached in free
jet expansions. Probably one of the most important of our papers it provided a model for
predicting the lower limits for those temperatures in terms of the gas properties in the source
and the nozzle Reynolds numbers, i.e. the temperature, pressure, composition of the source gas
and the nozzle diameter. In sum, it specified that state of the gas when the density became so
low that the molecular collision frequency vanished so that the values of all gas properties
governed by molecular collisions became frozen. In other words all properties, except density,
became frozen and did not change with further expansion. The continuing density decrease in
the absence of collisions is purely geometric and is due simply to the divergence of molecular
trajectories, undisturbed by collisions. Ron Andres and Dave Miller in our lab had already
shown that rotational degrees of freedom were cooled during free jet expansion. If we had
known anything about molecular spectroscopy we might have been smart enough to anticipate
by several years the classic experiments of Smalley, Wharton and Levy. They showed that the
cooling of rotational degrees of freedom during free jet expansion from small orifices
eliminated the rotational broadening of vibrational lines and made possible the elucidation for
the first time of the fundamental vibrational lines in the spectra of polyatomic molecules. Their
results made free jets the darlings of molecular spectroscopists so that there are many more such
jets used in spectroscopy experiments than in the scattering experiments for which they are
developed!
17. This paper was the first formal report on the ability of light carrier gases to accelerate heavy
molecules to supra-thermal energies. (Shortly after Lennard Wharton at Chicago got a big grant
from the Air Force to develop an electrostatic accelerator that would boost LiF molecules to
energies of 2 eV, Amos Horney, the director of AFOSR’s chemistry branch was in Princeton
and asked me to have lunch with him. I told him that I was impressed with all the publicity that
AFOSR and the University of Chicago had received on the start of that project. His face lit up
and he said: “John, if Lennard can get a 2eV beam of neutral molecules of LiF it will earn him
a Nobel Prize for sure.” (!!!!) I said: “Amos, come down to my lab after lunch and I’ll show
you beams with 3, 4 and 5 eV of translational energy.” He didn’t want to hear about it. A
couple of years later he called me one day and said that he had Lennard’s renewal proposal in
front of him and wanted to know what he should do. By that time Lennard had shown focusing
(important because the accelerator had some 500 accelerating elements and a beam path of 20
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feet) but had not yet achieved acceleration. (Ironically, Lennard had to use a free jet source to
get sufficient initial intensity to have useful intensity left after the 20 feet of travel). I said:
“Amos, Lennard has done the community a big favor. Everybody respects his ability so much
that if he gives up on this idea, nobody else will be tempted to waste some sponsor’s money
trying to sue electrostatic forces to accelerate molecules with dipole moments. Lennard is
sticking with the project only because he feels obligated to make good on his original proposal.
Give him his money and let him do something else.” Amos must have taken my advice because
the accelerator project was dropped, leaving Lennard and his colleagues free to come up with
the free jet spectroscopy tour de force and a number of elegant scattering experiments.
19. This study didn’t use free jets and didn’t attract much attention but it occupies a warm spot
in my heart. Up to then all measurements of thermal accommodation during molecule surface
collisions had been carried out, most notably by the late Lloyd
Smith (Univ. of Missouri), with a hot wire as the surface. The idea was that one could measure
the amount of power required to maintain the temperature of the wire at some level above that
of the amient gas which was at a low enough density so the mean free path was substantially
greater than the wire diameter. The electrical power to the wire equaled the rate of heat removal
by the gas. The wire dimensions were known so that the total number of collisions per unit time
could be readily calculated from the temperature and pressure of the ambient gas. Thus the
amount of energy picked up by each molecule during a single collision with the wire could then
be readily computed. The trouble was that at temperatures much above room temperature
radiation loss swamped the heat loss by the molecules so that measurements were limited to
relatively low temperatures. This paper describes a target mounted on a torsion wire so that it
loosely covered the aperature of an oven whose temperature could be maintained at any desired
value. By measuring the torsion required to keep the target in place as the oven temperature
changed we could measure the net momentum deposited by molecules hitting the target (all
Knudsen flow conditions). From that momentum change we obtained the translational energy
exchange per collision. Thus, we eliminated that radiation problem and obtained translational
energy accommodation coefficients at high target temperatures.
28 & 32. These experiments were fun. Because we buried two thermocouples in the substrate at
known distances from the surface we obtained the temperature gradient normal to the surface
and from the known distance between the surface and the nearest couple we got a good value of
the surface temperature. Time-of-flight velocity analysis of the departing molecules showed for
several species that they had Maxwellian velocity distribution corresponding to the surface
temperature. Kusch had shown that the velocity distributions of evaporating salt molecules
were Maxwellian but he didn’t know the surface temperature. I believe these experiments were
the first to show clearly that the distributions did match the surface temperature. The results
showed that for all the ammonium salts tried, including perchlorate, the evaporating vapor
comprised equimolar fluxes of ammonia and the corresponding acid. This finding was of
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substantial interest to “rocket scientists” because the vaporization mechanism of perchlorate had
long been a question in the combustion mechanisms of composite solid propellants, for most of
which perchlorate was the oxidant. (The first sentence in that paper said that if nuclear war ever
broke out the first step would be the vaporization of thousands of tons of ammonium
perchlorate. One reviewer strongly objected to this sentence but it was enthusiastically
endorsed by the other. The editor, Bryce Crawford at the time, left up to me the decision of
whether it should be omitted. It remains in place.)
29. I got interested in this problem because my friend Michel Boudart had gone to a meeting on
evaporation inhibition by compressed monomolecular films at which La Mer had proposed that
such films were physical barriers to the migration of water molecules. Michel didn’t understand
why such films also seemed perfectly permeable to oxygen molecules. Uri Navon built a
Langmuir through and developed a probe by which we could rapidly measure the rate of water
evaporation from a well defined surface area under well defined conditions. To make a long
story short we found that at least 40 per cent of the films effect on evaporation of water was due
to its acting as a rigid boundary that by viscous effects inhibited natural convention in the
substrate liquid, thus slowing down such convection in the Benard cells that transported surface
water cooled by evaporation down into the body of the liquid, replacing it with warmer water
from below. In the absence of such a film the water has a free surface which doesn’t resist such
recirculation. Thus a large fraction of the evaporation inhibition was due simply to
hydrodynamic effects.
31 & 33 stemmed from a study of surface diffusion of stearic acid on alumina. At the time the
results were the most unequivocal measures of surface diffusion rates that had ever been made, I
believe. A fascinating finding was the dependence of that rate on the amount of water absorbed
on the surface. The rate increased by three orders of magnitude as the water coverage increased
from zero to almost a monolayer and then went back down to lower than the original value as
coverage increased above a monolayer.
34, 35, 36, 50, 51, 54, 59, 61, 73, 89 Very rapid relaxation rates are difficult to measure by the
widely used method of measuring dispersion of ultrasonic waves. Dave Miller and Ron Andres
in our lab at Princeton had managed to measure the rotational relaxation rate in nitrogen (very
fast) by velocity analysis of molecules sampled at various distances along the free jet axis.
Such analysis provided the translational energy directly. An energy balance then gave the
amount of energy left in rotation. The experimental problems were severe because it is very
difficult to extract an undisturbed sample (i.e. without skimmer interference) except at large
axial distances (low jet densities) where most of the relaxation is over. Bob Gallagher and I
guessed that we might do better by appropriate modeling of the jet expansion by MOC analysis
and finding the relaxation rate that best fit the terminal rotational energy content obtained by the
energy balance method used by Miller and Andres. The dependence of terminal rotational
energy on source pressure provided additional confirmation of the measured rates. In this way
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we avoided the sampling problems and could apply the method nozzles of any size. It all
worked like a charm. We used it to measure the rotational relaxation rate of hydrogen at
temperatures up to almost 2000 K. (ultrasonic dispersion cannot work at high temperatures.)
The most interesting finding was an apparent resonant exchange between the 8th
rotational level
and the 1st vibrational level. The net result is that at temperatures high enough for the rotational
ladder to be available, the vibrational collision number for hydrogen is around 300, the same as
for rotation. This finding enabled people to understand some anomalous observations in shock
tubes. It also provided an explanation for deficits in populations of hydrogen molecules in the
8th
rotational energy level that had been found by astronomers. Bob subsequently made
measurements of rotation relaxation rates for a large number of molecules. Some have been
published but most of them are available only in his thesis. Further relaxation studies were
carried out by several of my later colleagues. i.e. 54, 59, 61, 73, 89.
37. This paper with Jimmy Searcy, contains the first experimental confirmation of a “magic
number” cluster formation. He found that the cluster comprising a proton with 21 water
molecules (probably an H30+, i.e. a solvated proton was unusually stable as shown by an
outsized abundance relative to other clusters. The discovery caused a bit of a stir at the time
because people who had been doing molecular dynamics calculations for nucleation
condensation in cloud chambers had found an energy minimum at this level of solvation but
thought it too shallow to be observed experimentally. They were overjoyed at the result.
Looking for and explaining such magic numbers has since become a big thing in clusters. They
have been of much interest in the subsequent expansion of cluster science and technology. The
most famous example of magic number clusters are those with 60 atoms of carbon (fullerenes or
“bucky balls”) that were also first discovered in free jet expansions of helium containing carbon
vapor. More recently my colleague Dongliang Zhan and I have revisited magic number
solvation, this time with ES ions of quaternary ammonium compounds. Paper 102 describes a
unique apparatus that brings about complete desolvation of ions before they are dispersed in a
bath gas containing precisely controlled concentrations of solvating species. The resulting ion-
gas mixture undergoes free jet expansion into a vacuum system containing a mass spectrometer.
The end result is that the solvation process is carried out under precisely controlled and
reproducible conditions. Results with alkyl substituted ammonium ions (RxNHy+) are described
in a paper cited in the section of the attached CV entitled “Preliminary Reports and Works in
Progress.” The noteworthy finding is that if y is two or more, the magic number of water
molecules attached to the ion is 20. If y is less than 2 the magic number of water molecules is
21! Apparently, the requirement for forming the stable icosahedron of 20 water molecules is
the availability of two hydrogens plus a charge, either an HOH+ or an RxNH2
+ will suffice. The
hydrogens are important probably because they facilitate hydrogen bonding. Moreover, these
magic numbers of 20 or 21 obtain even when the R’s are so big that the ion could not possibly
fit inside the 20 molecule icosohedron, the conformation that Castleman and others have
proposed for the structure of these magic number cluster ions. These Zhan-Fenn results seem
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more consistent with a proposal by Mautner and Kleeker that a 20 molecule icosahedron can
attach itself to an external host species.
It is provocative that the most famous and most stable cluster is buckminster fullerene
comprising 60 atoms of carbon. It turns out that the stable cluster of 20 water molecules also
has 60 atoms. We have also found (first paper in Preliminary Reports section at end of paper
list) that when methanol is the solvating species the magic number is 10. Ten molecules of
methanol also contain 60 atoms! Maybe this is a coincidence but very often coincidences in
science have led to fundamental understanding.
42. There has long been a big question about the evaporation coefficient of polyatomic
molecules from liquid surfaces. All previous measurements indicated very small values.
Sandra Lednovich and I found we could produce clean liquid surfaces in vacuo by partially
immersing in a pool of the liquid a metal disk rotating in a vertical plane. By viscous drag layer
of liquid on the disk was lifted out of the pool. Just before that layer passed in front of a
“window” into the vacuum system a “doctor-blade” scraped off the outermost layer so that the
surface exposed to the vacuum was clean a la Langmuir. The vaporizing flux from the liquid
was monitored by a small mass spectrometer. We were thus able to show that for glycerin and
several other liquids it was very close to one. This work came right after a paper by Somorjai
confirming that the value for glycerine was around 0.04 and that the evaporation was an
activated process!!!! I enjoyed pricking that balloon.
43, 46, 47, 81. These papers tell the story of our adventures with the Recycling Molecular
Beam Reactor, a device that I still think has lots of promise but have never done any more with
because the machine disappeared during a laboratory clean up! The important result was the
ability to separate and evaluate the effects of the three key variables, the vibrational energy of
cyclopropane and cyclobutane molecules incident on a hot surface, the translational energy of
those molecules, and the surface temperature. The vibrational activation energy turned out to be
that required to break a C-C bond in cyclopropane. The translational and surface energies (the
latter being the slope of an Arrhenius plot of rate vs. surface temperature) were mutually
interchangeable. Their sum always added up to 105 kJ/mol!
49, 58, 63. These papers summarize our long and painful study of the excitation of the
asymmetric stretch mode of CO2 by high energy collisions with nitrogen molecules. It was an
experimental tour de force that gave the Air Force the numbers it wanted for about one tenth of
the money it had spent on effort at Cornell Aeronautical Labs, which did not give any useful
results. I got some satisfaction out of that but a most important consequence of the study was
our acquisition of a Fourier Transform IR spectrometer with which we finally obtained the
rotational distributions shown in 63. The bigger reward was that spectrometer’s leading us into
the more interesting studies of the internal energies in molecules scattered by or formed at, hot
surfaces. (Next section.)
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56, 77, 78. These papers describe work on the spectral measurement of internal energy
distribution of nascent C02 molecules formed on an oxygenated platinum surface. We believe
these were the first ever such measurements. They showed how the reaction energy was
distributed among the various “sinks” including the surface and the internal degrees of freedom
of the product molecules. The results also gave some insight on the reaction mechanisms.
61, 73, 89. The work in these papers was another byproduct of our getting the FTIRS from the
Air Force. We were so embarrassed at not getting any results for a long time on the rotational
distribution of C02 molecules excited by collisions with nitrogen that in desperation we took
some spectra of the terminal states of C0 and C02 molecules in a free jet from a hot nozzle. We
found that the departures from Boltzmann distributions increased as the source gas temperature
decreased. Intrigued by this observation we wanted to go to still lower source temperatures. In
order to obtain sufficient vibrational excitation for emission spectra, we used a corona discharge
in the nozzle. We found indeed that the departure from Boltzmannality did increase further as
the source temperature was lowered. However, the most important results I have not yet had a
chance to write up. For one, we found that at room temperature in the source gas the emission
band due to C02 from carbon 13 had 15 per cent of the intensity of the band from carbon 12 C02
even though the relative abundance of carbon 13 is only one per cent. The answer seems to lie
in the 75 wave number difference in the energy levels of the two isomers. An excited carbon 12
isomer can excite a carbon 13 isomer with the excess 74 wave numbers being soaked up in
rotational and/or translational energy. But that energy is then locked in the heavy isomer
because in collisions with an unexcited light isomer it lacks the missing 75 wave numbers. The
net result is an accumulation of energy in the heavier isomer. A still more interesting results
was that a source temperatures low enough to bring about clustering we found a marked
decrease in the radiation lifetime, i.e. a marked increase in the radiation intensity at the same
source density. For example, a ten degree decrease in source temperature and constant source
density resulted in a fivefold increase in radiation intensity. We think this enhancement may be
due to an alignment of dipoles in a transient dimer. A theoretical paper by Liveer, Nitzan,
Amirav and Jortner indicated that such alignment could substantially decrease the radiation life
time of an excited molecule. (JCP 88, 3516, 1988).
65, 67, 85, These papers summarize our studies of the excitation of internal degrees of freedom
in molecules incident on a hot surface. To my knowledge, except for some rudimentary
observations by Marsden on rotational excitation of nitrogen colliding with a surface, our results
were the first definitive observations on the excitation of both rotation and vibration in
molecules indicent on a hot surface. I presume there has been a lot more work since that I have
not kept up with.
66. This paper was in response to a paper published by Kathy Saenger when she was Dudley
Herschbach’s student at Harvard. I had some doubts about her methodology and did the
calculations (on a pocket calculator) while I was in Germany. I invited her to be a co-author
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and she was happy to check everything out. She remains the only co-author I have never even
met!! As far as I know this is the only study on this subject that has ever appeared. So many
people now use pulse nozzles that one would think there would have been more activity on this
problem.
68, 69. The first two papers on Electrospray Ionization. Interestingly enough, the first
presentation of the first one was at the Fennfest which Gary Haller organized back in 1984. I
had a sneaking notion at the time that we were on to something but I had no idea how big it was.
74. This paper is widely cited, probably in part because it appeared in Analytical Chemistry, a
widely circulated journal, and in part because it was the first reduction to practice of what has
become one of the most widely used analytical techniques. i.e. the coupling of Liquid
Chromatograph with a Mass Spectrometer. I hadn’t thought the resulting paper was all that
significant because the chromatography was pretty bad. Nevertheless, because it was
apparently the first attempt to combine LC with ESIMS it was included in the collection of
papers comprising a volume entitled “Milestones in Analytical Chemistry” published in 1994 to
commemorate the 65 years of that journals’ life.
84, 87. The Zeit. Phys. D paper was the first formal publication of the results of ESMS of
proteins that really started the ES revolution. That issue of the journal commemorated Otto
Stern’s 100th
birthday anniversary and was somewhat delayed. The Science article contains
roughly the same material and came later but is much, much more widely cited, in well over
1000 papers, I’m told.3 The first public disclosure of the protein results was made at the June
1988 meeting of ASMS and is contained in the published abstracts but nobody references that
publication. (One of the reasons the Science article is more widely cited is that its date is later
than papers by authors who repeated our results shortly after that ASMS meeting.
Consequently, a casual look at the references in their papers suggests that they were the first to
obtain MS results with big molecules! That kind of gamesmanship is common in mass
spectrometry circles. I kid you not.) Anyway, this paper was the trigger for what has been
called “The Electrospray Revolution”. After it appeared the total number of papers published
on ESIMS went from less than ten a year in 1988 to over 1200 a year in 1999 and still seems to
be climbing! Also noteworthy is that paper number 90 has been cited over 800 times even
though it appeared in a journal with a circulation of only 500!
86. This paper sets forth the principles for deconvoluting the multiply peaked spectra that result
from multiple charging of ions of large molecules. Most of the programs used today for that
purpose are direct descendants of the methods in this paper. In importance it is second only to
the discovery that proteins could form multiply charged ions.
3 3,610 citations by August 2011. 21 years after publication it still receives over 200 citations/year.
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92. I think this paper is much more of a milestone than people realize. It was the first to show
that electrospray ionization was gentle enough to form ions from complexes held together by
noncovalent bonds, an ES ability that has created a lot of excitement because people think it is
unexpected. They don’t appreciate the fact that the plurality of the relatively weak non-covalent
bonds that can bind large molecules together add up to a very large stability of the complex.
More important, I think, is that this paper shows the ability of ES ionization to interrupt the
nucleation precipitation of a solid phase from a saturated solution at intermediate stages just as
free jet expansion can interrupt the precipitation of a condensed phase from a saturated vapor.
In other words, I believe that ESMS opens up opportunities for research on clusters of non-
volatile species formed by precipitation in supersaturated liquids. One of the e reasons this
paper has not received much notice, I think is that the Journal of Organic Mass Spectrometry
has a very limited circulation. The editor asked me to contribute to an issue honoring Jim
Morrison, an Australian mass spectrometrist who has been most kind to me and whom I admire
very much. This paper was ready at the time so that’s where it went.
94. The work covered by this paper was carried out by Takashi Nohmi, a postdoc who came
from Japan via Stanford. He was able to show that ES could produce intact ions of oligomers
with molecular weights up to 5,000,000. This capability had some implications with respect to
ion formation mechanism. We concluded that it constituted a case in which the Charged
Residue Mechanism originally proposed by Dole was applicable. Following that work others
have shown that intact ions can be formed from DNA oligomers with molecular weights up to
100 million or more! The group led by Dick Smith at Pacific Northwest Labs has been looking
at theses ions with the Fourier Transform Ion Cyclotron Resonance (FTICR) technique which
has sufficient resolution to determine both the mass of, and the number of changes on, a single
one of them. In addition, a former student of mine, Steve Fuerstenau, has been working at LBL
on TOF analysis of these very large ions while at the same time determining the number of
charges on them by a unique induction sensor. The goal of both groups is to map, and maybe
sequence, big chunks of chromosomes. Gary Siuzdak has shown that viruses can be passed
through an Electrospray Mass Spectrometer and recovered without losing their viability!
98. I honestly believe that this paper explains the ion formation process and behavior for large
molecules better than any other proposal but investigators simply don’t read it. I am aghast at
the nonsense that has been published and accepted on ion formation. People violate
conservation of charge and energy without batting an eye. Someday, I believe that this paper
will be recognized as embodying a good bit of truth. One problems is that the truth is fairly
intricate and most people are unwilling to take the time to think it through.
100. I am proud of this paper because it sets forth an experimental measurement of the field at
the surface of an ES droplet that is desorbing ions. I sent it to JACS and all three reviewers
rejected it for unbelievable reasons. I’m told that Mike Bowers never overrules his reviewers
even when they are dead wrong, as I believe they are in this case. The main thing that stuck in
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their craws is the idea that the charges on a droplet are distributed on it surface with
equidistance spacing. The inevitability of that distribution has been known since the days of
Ben Franklin, Farady and Gauss yet the reviewers don’t believe it! I simply can’t understand
how scientists can have such closed minds. I think another difficulty is that too many people
have been seduced by that simple minded presumption that ES ions can be identified with the
ions already in the bulk solution that by some means (they never say how) get transferred from
the solution into the gas phase. Shades of Phlogiston and the Caloric theory of heat!
106. It has been much lamented that electrospray can produce ions only from molecules
containing polar atoms or groups and thus can’t be used for analysis of hydrocarbons so that
fossil fuel materials are not suitable subject for ESIMS. This paper shows that in many if not
most of these materials the content of polar species is sufficiently high so that ESIMS provides
a lot of information on the composition of such materials as gasoline, jet fuel, Diesel fuel,
lubricants and even crude petroleum and coal1 Following our lead Alan Marshall with the ultra
high mass resolution provided by his Fourier Transform Ion Cyclotron Resonance (FTIC) mass
spectrometer has been able to detect and identify over 3000 polar species from a single mass
scan of a crude petroleum sample! Analysis of crude oil and coal have long posed formidable
problems. It may well be that ESIMS will be able to provide a lot of long sought answers to
questions on the origins of these materials.
I have said before, and will say again, that in my view much of what the Free-Jet-cum-ES Genie
can reveal still remains in the lamp. I ended the RGD paper “Where are we going with
molecular beams?” with the speculation that we might someday generate beams of biologically
important molecules and that someday most clinical laboratories might be equipped with
molecular beam machines. That paper was written in 1983 when we were just starting our
electrospray studies. Five years later the “Of Protons or Proteins” paper in the Stern issue of
Zeit. F Physik showed that beams of biologically important molecules could be produced and
ended with the question as to whether they could help investigators “coax the marvelously
complex molecules of living systems into surrendering vital secrets?” In another five years, as
mentioned in the 19 June C&E News cover (1995) story, ESMS was beginning to open a
window on protein conformation in solution, was allowing Fred McLafferty to study HD
exchange in gas phase protein ions and its dependence on conformation, and had enable Don
Hunt to identify the particular peptides on a cell surface that revealed the presence of melanoma
in the cell and signaled the immune system to destroy it! I can hardly wait to learn what another
five years will uncover. I tend to be overly enthusiastic perhaps, but I honestly believe that “we
ain’t seen nuthing’ yet!”
12
PUBLICATIONS 4
1 “The ignition of High Velocity Streams of Combustible Gases by Heated Cylindrical
Rods,” with J.W. Mullen, M.R. Irby; Third Symposium on Combustion, Flame and
Explosion Phenomena, Williamsand Wilkins (Baltimore) 1949.
2 “Burners for Supersonic Ramjets – Insatiability in Two-Inch Ramjet Burner,” with H. B.
Forney, R.C. Garmon; Ind. and Eng. Chem. 43, 1663 (1951).
3 “Lean Flammability Limit and Minimum Spark Ignition Energy,” Ind. and Eng. Chem.
43, 2865 (1951).
4 “The Effect of Flameholder Geometry on Combustion Efficiency in Ducted Burners,”
with E.C. Wilkerson; Fourth Symposium on Combustion, Williams and Wilkins
(Baltimore) 1953, p. 231.
5 “Activation Energies in High Temperature Combustion,” with H.F. Calcote: Fourth
Symposium on Combustion, Williams and Wilkins (Baltimore) 1953, p. 749.
6 “High Intensity Molecular Beam Apparatus,” with J. Deckers; Rev. Sci. Inst. 34, 96
(1963).
7 “Molecular Beams from Nozzle Sources,” with J. Deckers; Third International Rarefied
Gas Dynamics Symposium, Vol 8, Academic Press (New York) 1963, p. 497.
8 “Separation of Gas Mixtures in supersonic Jets,” with V. H. Reis; J. Chem. Phys. 39,
3240 (1963).
9 “Recovery Factor Measurement in Gas Mixtures,” with G. Maise, Phys. of Fluids 7,
1080 (1964).
10 “High Intensity and High Energy Molecular Beams,” with J.B. Anderson, R.P. Andres;
Advances in Atomic and Molecular Physics, Vol. I, Academic Press (New York)
1965, p.345.
11 11 “Supersonic Nozzle Beams,” with J.B. Anderson, R.P. Andres; Advances in
Chemical Physics, Vol. 10, Wiley Inerscience (New York) 1966.
12 “Velocity Distribution in Molecular Beams from Nozzle Sources,” with J.B. Anderson;
Phy. of Fluids 8, 780 (1965).
4 This bibliography is copied from the one provided by J. B. Fenn to go along with his self-evaluation. Reference
109 is off-chronological sequence as it was not included in Fenn’s list.
13
13 “Background and Sampling Effects in free Jet Studies by Molecular Beam
Measurements,” with J.B. Anderson; Rarefied Gas Dynamics Fourth Symposium-
Toronto, 1964, Academic Press, 1966.
14 “Studies of Low Density Supersonic Jets,” with J.B. Anderson, R.P. Andres, G. Maise;
Rarefied Gas Dynamics Fourth Symposium, Toronto, 1964, Academic Press, 1966.
15 “Supersonic Nozzle Beams – Some Recent Experimental Results,” with N. Abuaf, J. B.
Anderson, R.P. Andres; presented at AGARD Colloquium on Recent Advances in
Aerothermochemistry, AGARD Conference Proceedings No. 12, 1967.
16 “Field Ionization Gauge for Molecular Beam Detection,” with R.O. woods; Rev. of Sci.
Inst. 37, 917 (1966).
17 “Molecular Beams at Energies Above One Electron Volt,” with N. Abuaf, J.D. Anderson,
R.P. Andres; Science 35, 997 (1967).
18 “Studies of Low Density Supersonic Jets,” with N. Abuaf, J.B. Anderson, R.P. Andres,
D.R. Miller; Rarefied Gas Dynamics, Vol. II (C.L. Brundin, ed.) Academic Press
(New York) 1967.
19 “Measurements of Momentum Accommodation of Gs Molecules at Surfaces,” with J. B.
Anderson, R.N. Kostoff; Fundamentals of Gas-Surface Interactions (H. Saltsburg, J.
Smith, and M. Rogers, eds.) Academic press (New York) 1967.
20 “Molecular Beam Engineering at Intermediate Energies,” Entropie 18, 33 (1967).
21 “A Phalanx Flame Model for Combustion of Composite Solid Propellants,” Comb. and
Flame 12, 201 (1968).
22 “Molecular Beam Experiments in the Lunar Environment,” with J.B. Anderson, D.G. H.
Marsden; Proc. Of the 3rd
Lunar International Symposium, Belgrade 1967 (F.J.
Malina, ed.) Program Press, 1969.
23 “New Methods for Producing High Energy Molecular Beams,” with J.B. Anderson; Proc.
Of AGARD Colloquium on New Experimental Techniques for Propulsion and
Energetics Problems, Munich, 1967.
24 “Viscous Effects on Impact Pressure Measurements in Low Density Flows at High Mach
Numbers,” with J.H. Chang; Rarefied Gs Dynamics Sixth Symposium, Vol., I,
Academic Press (New York) (1969) p. 855.
14
25 “Strand Size and Low Pressure Deflagration Limit in a Composite Propellant,” with R. A.
Cookson; presented at the 7th
Aerospace Sciences Meeting AIAA, New York, January
1969, AIAA J. 8, 864(1970).
26 “Species Separation by Stagnation of Argon-Helium Mixtures in Supersonic Flow,” with
J. H. Chang; Proc. 7th
Int. Symp. On Rarefied Gas Dynamics, Pisa, Italy, July 1970.
27 “Velocity Distribution of Several Gases Scattered from High Temperature Surfaces,”
with S.P. Tang, A. Casuto; ibid.
28 “Some Applications of Molecular Beam Velocity Spectroscopy to Evaporation and
Energy Exchange,” with S.P. Tang; Entropie 42, 51 (1971).
29 “Interfacial mass and Heat Transfer During Evaporation: I. An Experimental Technique
and Some Results with a Clean Water Surface; II, Effect of Monomolecular Films on
Natural Convection in Water” with Uri Navon; AIChE J. 17, 131 (1971).
30 “Thermal Recovery Factors in Supersonic Flows of Gas Mixtures,” with G. Maise; J.
Heat Trans. 94-C, 29 (1972).
31 “Modification to the Higashi Model for Surface Diffusion,” with R.T. Yang, G.L. Haller,
AIChE J. 19, 881 (1973).
32 “Vacuum Sublimation of Ammonium Perchorate,” with S.P. Tang; J. Phys. Chem. 77,
940 (1973).
33 “Surface Diffusion of Stearic Acide on Aluminum Oxide,” with R.T. Yang, G.L. Haller;
AIChE J. 20, 735 (1974).
34 “Relaxation Rates from TOF Analysis of Molecular Beams,” with R.J. Gallagher; J.
Chem. Phys. 60, 3487 (1974).
35 “Rotational Relaxation in Hydrogen,” with R.J. Gallagher; ibid., 3492.
36 “A free Jet Study of Rotational Relaxation in Nitrogen,” with R. J. Gallagher; Proc. 9th
Int. Symp. On Rarefied Gas Dynamics, Goettingen, July, 1974.
37 “Clustering of Water on Hydrated Protons in a Supersonic Free Jet Expansion,” with J.Q.
Searcy; J. Chem. Phys. 61, 5282 (1974)
38 “Scattering of an Argon Beam by a Liquid Glycerine Surface,” with M.P. Sinha; proc. 5th
Int. Symp. on Molecular Beams, Nice, April 1975.
39 “Some Observations on Condensation in Free Jets,” with R.J. Gallagher, R.T.V. Kung;
ibid.
15
40 “Total Cross Section measurements for the Scattering of Argon by Aliphatic
Hydrocarbons,” with T. Nenner, H. Tien; J. Chem. Phys. 63, 5439 (1975).
41 “Long Range Attractive Forces for Hydrogen-Light Hydorcarbon Pairs,” with H. Tien, T.
Nenner; AIChE J. 22, 405 (1976).
42 “Absolute Evaporation Rates for some Polar and Nonpolar Liquids,” with S. L.
Lednovich; AIChE J. 23 454 (1977).
43 “Recycling molecular Beam Reactor,” with G. Prada-Silva, K. Kester, D. Loffler, G. L.
Haller; Rev. Sci Inst. 48, 897 (1977).
44 “Experimental Determination of the Discharge Coefficients for Critical Flow Through an
Axisymmetric Nozzle,” with S.P. Tang; AIAA J. 16, 41 (1978).
45 “On the Calibration of Mass Spectrometers for van de Waals Dimers,” with Naisin Lee;
Rev. Sci. Inst. 49, 1269 (1978).
46 “The Role of Vibrational Energy in Surface Isomerization of Cyclopropane,” with G.
Prada-Silva, D. Loffler, B.L. Halpern, G.L. Haller; Surf. Sci. 83, 455 (1979).
47 “Molecular Beam Study of the Isomerization and Dehydration of Butene on a Mica
Surface,” with D. Loeffler, G.L. Haller; J. Catal. 57, 96 (1979).
48 “Angular Distribution of Fluorescence from Liquids and Monodispersed Spheres by
Evanescent Wave Excitation,” with E. H. Lee, R.K. Chang; Applied Optics 18, 862
(1979).
49 “Vibrational Excitation of CO2 by Collisional T-V Exchange,” with C.E. Kolb, S.B.
Ryali; presented at the VII International Symposium on Molecular Beams, Riva del
Garda, Italy, 28 may – 2 June 1979.
50 “Internal Energy Relaxation Rates from Observations on Free Jets, “with C.G. M. Quah,
D. R. Miller; in Rarefied Gas Dynamics (11th
Symp, R. Campargue ed.) Vol. II p. 885
CEA, Paris, 1979.
51 “Internal Energy Relaxation in Methane and its Chlorinated Derivatives,” with R.J.
Gallagher; ibid., p. 935.
52 “Order from chaos with Molecular Beams,” Proc. Of the Indian Academy of Science
(Chemical Sciences) 89, 309 (1980).
53 “Dimer Depletion by Solute Species in Free Jet Expansion,” with M. Yamashita, T. Sano,
S. Kotake; J. Chem. Phys. 75, 5355 (1981).
16
54 “Flowfield Calculations in Nonequilibrium Free Jets by the Method of Characteristics,”
with M. Labosky, S.B. Ryali, D.R. Miller; in Rarefied Gas Dynamics (S.S.
Fisher,ed.) Prog. In Astro. And Aero. 74, 695 AIAA (1981).
55 “Simplified Kinetic Treatment of Heavy Molecule Velocity Persistence Effects:
Application to Species Separation,” with J. Fernandez de la Mora, J. Mercer, D.E.
Rosner; ibid., 617.
56 “The exciting Oxidation of CO on Pt,” with D.A. Mantell, S.B. Ryali, G. L. Haller Chem.
Phys. Lett. 81, 185 (1981).
57 “Surface Catalyzed Production of N2O from the Reaction of N Atoms and O2 on
Platinum,” with E. J. Murphy, B. L. Halpern; J. Catal. 74, 434 (1981).
58 “Collisional Excitation of CO2 by N2 O2 and Ar”, with S.B. Ryali, C. E. Kolb, J.A.
Silver; J. Chem. Phys. 76 5878 (1982).
59 “Rotational Energy Distribution in Free Jets of CO2,” with S. P. Venkateshan, S.B. Ryali;
presented at the VIII Int. Symp. on Molecular Beams, Cannes, June 1981.
60 “Clusters as a Source of Error in Molecular Beam Scattering Experiments,” with H. Tien,
P. J. Gale, S. B. Ryali; Chem. Phys. Lett. 93, 213 (1982).
61 “Terminal Distributions of Rotational Energy in Free Jets of CO2 by Infrared Emission
Spectrometry,” with S. P. Venkateshan, S. B. Ryali; J. Chem. Phys. 76, 2599 (1982).
62 “Collision Kinetics in Gas Dynamics,” in Applied Atomic Collision Physics, Vol. 5 (E.
W. McDaniel, ed.) Academic Press (New York) 1982, p. 34.
63 “High resolution Emission Spectroscopy of CO2 Vibrationally Excited by Collision with
N2,” with S.P. Venkateshan and S. B. Ryali; Chem. Phys. Lett. 92, 606 (1982).
64 “Research in Engineering,” in Chemical Engineering Education, 190 (Fall 1982).
65 “Distribution of Internal Energy in CO and CO2 Vibrationally Excited by a Hot Platinum
Surface,” with D. A. Mantell, G. L. Haller, S. B. Ryali; J. Chem. Phys. 78, Part II,
4250 (1983).
66 “On the Time Required to Reach Fully Developed Flow in Pulsed Supersonic Free Jets,”
with K. L. Saenger; J. Chem. Phys. 79, 6043 (1983).
67 “Distribution of Internal Energy in NO Vibrationally Excited by a Hot Platinum
Surface,” with D. A. Mantell, Y F. Maa, G. L. Haller, S. B. Ryali; J. Chem. Phys. 78,
6339 (1983).
17
68 “The Electrospray Ion Source – Another Variation of the free Jet Theme,” with
Masamichi Yamashita; J. Phys. Chem. 88, 4451, (1984).
69 “Negative Ion Production with Electrospray Ion Source,” with Masamichi Yamashita; J.
Phys. Chem. 88, 4671 (1984).
70 “Clustering in Free Jets – Aggregation by Dispersion,” with S. B. Ryali; Ber. Bunsenges.
Phys. Chem. 88, 245 (1984).
71 “Dimer Formation in HF at Low Densities—Between Knudsen and Kantrowitz,” with J.
P. Toennies, M. Mann K. Muller, E. L. Knuth; Rarefied Gas Dynamics (14th
International Symposium, H. Oguchi, ed.) vol. 2 p. 733, Univ. Tokyo Press (1985).
72 “Ion Pumping and Free Jet Expansion,” with C. M. Whitehouse, M. Yamashita, C. K.
Meng; ibid, p. 857.
73 “Terminal Distributions of Rotational Energy in Free Jets of CO and CO2,” with S. B.
Ryali, S. P. Venkateshan, ibid, p. 567.
74 “Electrospray Interface for Liquid Chromatographs and mass Spectrometers, with C. M.
Whitehouse; Analytical Chemistry 57, 675, (1985).
75 “Performance Characteristics of the Electrospray Ion Source,” with C. M. Whitehouse, C.
K. Meng, Y. Q. Shen, M. Menn, S. F. Wong; 33rd Annual Conf. Mass Spect. Allied
Topics, (R. Finnigan, ed.) ASMS, May, 1985.
76 “Where Are We Going With Molecular Beams?” in Rarefied gas Dynamics, Vol., 2, O.
M. Belotserkovski, M. N. Kogan, S. S. Kutateladze and A. K. Rebrov, ets., (Plenum
Publishing Corporation 1985).
77 “They Dynamics of CO Oxidation on Pt from Translational, Rotational and Vibrational
Excitation in Product CO2,” D. A. Mantell, K. K. Kunimori, S. B. Ryali, G. L. Haller;
Surface Sci. 172, 281 (1986).
78 “Coverage Effects in Catalytic Time-Resolved Infrared Emission Studies of Surface
Catalysed Oxidation of CO, “ with K. Kunimori, D. A. Mantell, S. B. Ryali, G. L.
Haller; Proc. Of International and Colloqium on Advances in Molecular Reaction
Dynamics, R. Vetter and J. Vigue, eds., CNRS, Paris 333, (1986).
79 “The Electrospray Ion Source – Features and Applications,” with M. Yamashita, Y. Q.
Shen, and C. K. Meng; Proc. Int’l. Workshop on Cluster Ion Beams, Tokyo-Kyoto
(1986).
18
80 Further Adventures with an Electrospray Ion Source,” with C. M. Whitehouse, F. Levin,
and C. K. Meng; 34 Annual Conf. Mass Spect. Allied Topics (E. C. M. McEwendy),
p. 502, ASMS (June, 1986).
81 “Effect of Incident Translational Energy on the Surface-Induced Isomerization of
Cyclopropane,” with L. Tsou and G. L. Haller; J. Phys. Chem. 91, 2654, (1987)
82 “Multiple Charging in Electrospray Ionization of Poly(ethylene glycol)s,” with S. F.
Wong and C. K. Meng; J. Phys. Chem. 92, 546,(1988).
83 “Microjet Burner for Molecular-beam Sources and Combustion Studies, “with W.
Groerger; Rev. Sci. Instr. 59, 1971, (1988).
84 “Of protons or proteins ‘ “A Beam’s a beam for a’ that.” (O.S. Burns) with C. K. Meng
and M. Mann; Z Phys. D. – 10 Atoms, Molecules, and Clusters, 10, 361-368 (1988).
85 “Internal Energy Distribution of OCS Desorbing from Hot Platinum Surface,” with W.
Groeger; J. Phys. Chem. 93, 344-349, (1988).
86 “Interpreting Mass Spectra of Multiply Charged Ions,” with M. Mann and C. K. Meng;
Analytical Chemistry 61, 1702, (1989).
87 “Electrospray Ionization for Mass Spectrometry of Large Biomolecules,” with M. Mann,
C. K. Meng, S. F. Wong, and C. M. Whitehouse, Science 246, 64, (1989).
88 “Structure of Symposium Test Peptide-3,” with J. Elliot, K. Stone, W. Roberts, M.
Lopresti, R. DeAngelis, M. Crawford, J. Kapouch, E. Jacobsen, K. Williams, W. J.
McMurray, C. K. Meng, and M. Mann in Techniques in Protein Chem. (T.E. Hugli,
ed) 569, Acad, Press (1989).
89 “Rotational Relaxation in CO and CO2 in Free Jets of Gas Mixtures,” with T. Kodama,
and S. Shen in Rarefied Gas Dynamics (E. P. Muntz et al., eds.) Prog. In Astro. and
Aero. 117, 68 (1989).
90 “Electrospray Ionization – Principles and Practice,” with M. Mann, C.K. Meng, and S. F.
Wong; Mass Spectrometry Reviews 9, 37 (1990).
91 “Where Do all the Charges Go in Electrospray Ionization,” (with M. Mann and S. F.
Wong) in Ion Formation from Organic Solids, Proceedings IFOS-V, Lovanger,
Sweden, June 1989; (A. Hedin., B.U.R. Sundqvist, and A. Benninghoven, eds.), pg.
139, John Wiley – 1990.
92 “Formation of Charged Clusters During Electrospray Ionization of Organic Species,”
with C. K. Meng; Org. Mass Spectrometry 26, 542 (1991).
19
93 “An Ion-Storage Time-of Flight Mass Spectrometer for Analysis of Electrospray Ions,”
with J. G. Boyle, C. M. Whitehouse; Rapid Commun. In Mass Spectrometry 5, 400,
(1991).
94 “Electrospray Mass Spectrometry of Poly(ethylene glycol)s with Molecular Weights Up
to Five Million,” with Takashi Nohmi; J. Am. Chem. Soc. 114, 3241 (1992).
95 “Electrospray Mass Spectrometry” with M. Mann, in Mass. Spectrometry in the
Biological Sciences: A Tutorial (M. L. Gross, ed.) Kluwer Academic Publishers; The
Netherlands, 1992, p. 145.
96 “Electrospray Mass Spectrometry – Principles and Practice”, with M. Mann, in mass
Spectrometry. Clinical & biomedical Applications, Vol. 1, p.1, D. Desiderio, ed.,
Plenum Press, 1993.
97 “Three Dimensional Deconvolution of Multiply Charged Spectra,” with J. M. Labowsky,
and C. M. Whitehouse; Rapid Commun in Mass Spectrometry 7, 71, (1993).
98 “Ion Formation from Charged Droplets: Roles of Geometry, Energy and Time,” J. Amer.
Soc. Mass Spectrom. 4, 524 (1993).
99 “Electrospray Ion Formation: Desorption versus Desertion,” with T. Nohmi, S. Shen, and
J. F. Banks, Jr. Am. Chem. Soc. Symp. Series, 619, 60-80 (1995).
100 “In Electrospray Ionization, How Much Pull Does an Ion Need to Escape Its Droplet
Prison,” with C. K. Meng, and J. Rosell; J. Am. Soc. Mass Spectrometry, 8, 1147
(1997).
101 “Determining the Composition of Liquid Droplets in a Gas of Different
Composition,” with P. Kiseley and J. Rosell, Ind. & Eng. Chem Res. 36, 3081
(1997).
102 “Solvation studies of Electrospray Ions – Methods and Early Results” with D. Zhan
and J. Rosell, J. Am Soc Mass Spectrom. 9, 1241-1247 (1998)
103 “Reflections on Electrospray mass Spectrometry of Synthetic Polymers,” with M.
Maekawa, T. Nohmi, D. Zhan and P. Kiselev, J. Mass Spectrom Soc. Japan, 47(2),
76-83(1999)
104 “Mass Spectrometry: Electrospray Ionization” in Encyclopedia of Spectroscopy and
Spectrometry (John Lindon, George Tranter andJohn Holmes, eds.) Academic Press,
London (1999)
20
105 “ A Continuum Model for Ion Evaporation from a Drop: Effect of Curvature and
Charge on Ion Solvation Energy” with M. Labowsky, and J. Fernandez de la Mora.
Anal. Chim. Acta 406, 105-110 (2000)
106 “Electrospray Mass Spectrometry of Fossil Fuels,” with D. Zhan, Int. J. Mass
Spectrom. 194; 197-208 (2000)
107 “On the Significance of ‘Electrochemistry’ in ESIMS” with J.F. de la Mora, G.J. Van
Berkel, C.G. Enke, R.B. Cole, and M. Martinez-Sanchez (in Special Feature
Discussion of Electrochemical Processes in Electrospray Ionization mass
Spectrometry”, Graham Cooks, ed) Journal of Mass Spectrometry 35, 939-952
(2000)
108 “Mass Spectrometric Implications of High Pressure Ion Sources” International
Journal of Mass Spectrometry 200 (2000) 459–478
109 RESEARCH IN RETROSPECT: Some Biograffiti of a Journeyman Chemist, Ann. Rev.
Phys. Chem. 1996.47:1-41
Preliminary Reports and Works In Progess
“Magic Numbers in Hydration of Amines and Ammonium Compounds,” with D. Zhan. Proc.
46th
ASMS Conf. Mass Spectrom. Allied Topics, June 1998, p. 424 (Journal paper in
preparation)
“Gas Phase Hydration of Electrospray Ions from Small Peptides,” with D. Zhan, Proc. 46th
ASMS Conf. Mass Spectrom. Allied Topics, June 1998, pg. 146 (Journal paper in
preparation)
“Extensive Hydration of Electrosprayed Singly Charged Tetrahelptyl Ammonium Ions Using
a Novel Desolvation-Resolvation Source” with J. C. Hannis, D. Zhan, and D. C. Muddiman,
ICR Ion Trap News Letter #53, Winter 1999, p. 6.
“An ESI-MS Perspective on Protein Refolding”, D. Zhan, presented at the 47th
ASMS Conf.
Mass Spectrom. Allied Topics, June 1999 (Proceedings on CD available from ASMS, Santa
Fe, NM Journal paper in preparation.)
21
U.S. Patents
2,468,734 “Condensation of olefinic compounds with hydrogen sulfide” with J. L. Eaton
Assigned to Sharples Chemicals, Inc. Issued 5/3/49
2,481,583 “Condensation of olefinic compounds with hydrogen sulfide” with J. L. Eaton
Assigned to Sharples Chemicals, Inc. Issued 9/13/49
2,648,196 “Ramjet burners with aqueous injection to promote smooth burning” with J. W.
Mullen, II. Assigned to Experiment, Inc. Issued 8/11/53
2,722.553 “Intense combustion for chemical synthesis” with J. W. Mullen, II.
Assigned to Chemical Construction Company. Issued ??/??/55
2,742,261 “Controlled Area Combustion for Ramjets” with J. W. Mullen, II
Assigned to Secretary of the Navy, Issued 4/26/56
2,878,644 “Sonic velocity submerged combustion burner”
Assigned to Experiment, Inc. Issued 3/24/59
3,010,279 “Method of operation of propulsion devices” with J. W. Mullen, II
Assigned to Texaco-Experiment, Inc. Issued 11/28/61
3,005,762 “Electric discharge jet stream.”
Assigned to Aerochem Research Labs. Issued 10/24/61
3,122, 418 “Method of making carbon black” with J. W. Mullen, II and F.I. Tanczos
Assigned to Texaco-Experiment, Inc. Issued 2/25/64
3,230,701 “Two step reaction propulsion method” with J. W. Mullen and F.I.
Assigned to ???? Issued 1/25/66
3,456,501 “Method and apparatus for separation of compounds from gaseous streams”
Assigned to Mobil Corp. Issued 9/9/69
3, 626,665 “Process for separating uranium isotopes” with J.R. White
Assigned to Mobil Corp. Issued 12/14/71
4,531,056 “Method and apparatus for the mass spectrometric analysis of solutions” with
M. J. Labowsky and M. Yamashita. Assigned to Yale Univ. Issued 7/243/85
22
4,542,293 “Process and apparatus for changing the energy of charged particles contained in
a gaseous medium” with M. Yamashita and C. R. Whitehouse Assigned to Yale
Univ. Issued 9/17/85
5,130,538 “Method of producing multiply charged ions and for determining molecular
Weights of molecules by use of the multiply charged ions and molecules”
With M. Mann and C. K. Meng. Assigned to Yale Univ. Issued 7/14/92
5,306,142 “Method and apparatus for improving electrospray ionization of solute species”
with C. R. Whitehouse, Shida Shen and Cawthon Smith
Assigned to Analytica of Branford, Inc. Issued 4/26/94
5,523,566 “Method for detection and analysis of inorganic ions in aqueous solutions
by electrospray mass spectrometry” with S. D. Fuerstenau Issued 6/14/96
5,581,080 “Method for determining molecular weight using multiply charged ions”
With C. K. Meng and M. Mann. Issued 12/3/96
5,686,726 “Composition of matter of a population of multiply charged ions derived from
polyatomic parent molecular species” with M. Mann and C. K. Meng
Issued 11/11/97