ir-uv photoionization and depletion spectroscopy of al- and cu-ethylenediamine complexes yuxiu lei,...
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IR-UV PHOTOIONIZATION AND DEPLETION SPECTROSCOPY OF Al- AND
Cu-ETHYLENEDIAMINE COMPLEXES
Yuxiu Lei, Jung Sup Lee, and Dong-Sheng Yang
Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055
Motivations
• Probe N-H and C-H stretch modes
• Structural identification (compared to ZEKE results)
• Larger clusters (multiple-ligand and multiple-metal)
Al-(Ethylenediamine) Cu-(Ethylenediamine)
Ethylenediamine (en)
Previous ZEKE Studies
1. Xu Wang and Dong-Sheng Yang, J. Phys. Chem. A, 2004, 108, 6449.
2. Shenggang Li, Jason F. Fuller, Xu Wang, Bradford R. Sohnlein, Paragranjita Bhowmik, and Dong-Sheng Yang J. Chem. Phys., 2004, 121, 7692.
IR-UV Experimental Schemes
IE
ν = 1ν = 0
100 ns
ν = 1ν = 0
100 ns
ν=0
Resonant 2-photon ionization(R2PI) ZEKE dip
IR
UV
UV
IR
R2PI Spectra of Cu- and Al-en
IR (cm-1)
2750 2850 2950 3200 3300 3400
Ion
inte
nsi
ty
Cu-en
Al-en
Cu-en
Al-en
N-HC-H
A. Diot et T. Theophanides, Canadian Journal of Spectroscopy, 17, 1972, 67-72.
IR Spectrum of Ethylenediamine
Experimental and Simulated IR Spectra of the Ligand
IR (cm-1)
IR (cm-1)
2750 2850 2950 3050 3150 3250 3350 3450
Cu-en
en
Al-en
C-H N-H
Comparison of Complexes with Ligand
IR (cm-1)
3250 3300 3350 3400 3450
Al-en N-H bands
IR (cm-1)
2800 2850 2900 2950 3000
Al-en C-H bands
IR (cm-1)
3250 3350 3450
Cu-en N-H bands
IR (cm-1)
2800 2900 3000
Cu-en C-H bands
IR (cm-1)
2800 2900 3000
Cu-en C-H bands
2950 2960
2950, C-H stretch 2960, C-H stretch
1351, C-H bend 1598, N-H bend
Fermi resonance: 2960 ≈ 2950 ≈ 1351+1598 = 2949
IR (cm-1)
2800 2900 3000
Cu-en C-H bands
2950 2960
IR (cm-1)
2800 2900 3000
Cu-en C-H bands
2950 2960
IR (cm-1)
2800 2900 3000
Cu-en C-H bands
2950 2960
IR (cm-1)
2920 2930 2940 2950 2960
R2PI and ZEKE Dip
R2PI
ZEKE Dip
Conclusions and Future works
ν = 1ν = 0
ν+ = 0ν+ = 1
• Measurement of N-H and C-H frequencies for neutral complexes
• Consistent with ZEKE results
• New schemes for ion frequency measurements
• Multiple-ligand and multiple-metal complexes