Nuclear Quadrupole Coupling in 1,1,1-Trichloroethane: Inertial and Principal Tensors for 35Cl and 37Cl.

ABSTRACT

The hyperfine structure in the J = 1 <-- 0 and J = 2 <-- 1 transitions of 35Cl3CCH3 and 35Cl237ClCCH3 was resolved by utilizing the sub-Doppler resolution of a pulsed supersonic beam, cavity Fourier transform microwave (FTMW) spectrometer. The complete inertial and principal quadrupole tensors of the chlorine nuclei are determined. The symmetric top treatment for 35Cl3CCH3 and the asymmetric top treatment for 35Cl237ClCCH3 are found to yield identical results for the principal tensor components of the 35Cl nucleus. The quadrupole asymmetry parameter eta for the chlorine nuclei in 1,1,1-trichloroethane is small, which indicates nearly cylindrical symmetry of the field gradient. Nevertheless, there is evidence for some deviation of the z symmetry axis of the field gradient from the direction of the C-Cl bond. Copyright 1998 Academic Press.