vibrational and hyperfine coupling effects in (hi) 2 s. p. belov, f. willaert, b. a. mcelmurry, r....

Vibrational and Hyperfine Coupling

Effects in (HI)2

S. P. Belov, F. Willaert, B. A. McElmurry,R. R. Lucchese, J. W. Bevan,

L. H. Coudert, and J. T. Hougen

Overview

•Interesting from the chemical point of view

•Analysis of the microwave data recorded at Texas A&M University

•Interesting from the physical point of view

•Hyperfine-rotational-vibrational energy levels

The hydrogen halide dimers family

(HF)2(HCl)2 (HBr)2 (HI)2

Dyke, Howard, and Klemperer, J. Chem. Phys. 56, 2442 (1972)

Schuder, Lovejoy, and Nesbitt, J. Chem. Phys. 99, 4346 (1993)

Chen, Hight Walker, Novick, and Tao, J. Chem. Phys. 106, 10386 (1997)Castillo-Chara, McIntosh, Wang, Lucchese, and Bevan,J. Chem. Phys. 120, 10426 (2004)

Present investigation.

The interconversion geared-type motion

The potential energy function V()

(HF)2(HCl)2 (HBr)2 (HI)2

E 0.66 15.5 15.0 17.1

Dyke, Howard, and Klemperer, J. Chem. Phys. 56, 2442 (1972)Schuder, Lovejoy, Lascola, and Nesbitt, J. Chem. Phys. 99, 4346 (1993)Castillo-Chara, McIntosh, Wang, Lucchese, and Bevan, J. Chem. Phys. 120, 10426 (2004)

The very large quadrupole moment

The iodine nucleus has a very large quadrupole moment.

The very large quadrupole coupling

The HI molecule displays a very large electric quadrupolecoupling constant.1

1. Chance, Varberg, Park, and Zink, J. Mol. Spec. 162, 120 (1993)

Accounting for the large quadrupole coupling

J matrix elements

I2 Hanes, Lapierre, Bunker, and Shotton, J. Mol. Spec. 39, 506 (1971)

v matrix elements

Hyperfine coupling Hamiltonian

Hyperfine coupling matrix elements

(CH2NH2)2 Merke and Coudert, J. Mol. Spec. 237, 174 (2006)

The measurements

Paper WJ02, McElmurry, Wang, Lucchese, Bevan, and Belov, Columbus 2006

The R(0), v transition

RMS 18 kHz Without v1 matrix elements, RMS 36 kHz

Spectroscopic constants

The R(3), v transition

Spin-rotation: I·J

Quadrupole distortion: J2, Q:V}