Ii. Ioannou et al., THE ROTATION-TUNNELING SPECTRUM OF ARGON-ACETALDEHYDE - THEORY AND ANALYSIS, Journal of molecular spectroscopy, 171(1), 1995, pp. 265-286
Citations number
20
Categorie Soggetti
Spectroscopy,"Physics, Atomic, Molecular & Chemical
The microwave spectrum of argon-acetaldehyde is split into quartets wh
ich are rotation-tunneling in character. Qualitatively, each asymmetri
c-rotor level is first split into an A and an E component by internal
rotation of the methyl group. These A and E components are then each f
urther split into another doublet, as the argon (effectively) tunnels
from a position above the acetaldehyde heavy atom plane to an equivale
nt position below that plane. The observed transitions (220 lines with
J less than or equal to 7) have been fitted to nearly experimental ac
curacy (8 kHz) using 29 parameters. The Hamiltonian was expressly desi
gned for the Ar-acetaldehyde system and was constructed using group-th
eoretical considerations and principles from the generalized internal
axis method formalism originally developed for the water dimer. This i
s the first application of the method to a case involving an inversion
motion and methyl internal rotation. (C) 1995 Academic Press, Inc.