The free-jet millimeter-wave absorption spectra of four isotopomers of difluoromethane krypton have been assigned. The krypton is in the HCH plane of difluoromethane, 3.616 (3) A ˚ from from its center of mass, and forms an angle of 64 (2) with the FCF plane. Ab initio and distributed polarizability model calculations confirm the observed conformation. The measured transitions are split into two component lines due to the tunnelling between two equivalent positions, with Kr above or below the FCF plane. The vibrational splitting, 79.19 (4) MHz, has been used to estimate the inversion barrier (1.23 (5) kJ mol1), while an estimate of the dissociation energy (1.9 kJ mol1) has been deduced from centrifugal distortion effects.
A. Maris, S. Melandri, W. Caminati, I. Rossi (2005). Free-jet rotational spectrum and tunneling motion in difluoromethane–krypton. CHEMICAL PHYSICS LETTERS, 407, 192-198 [10.1016/j.cplett.2005.03.074].
Free-jet rotational spectrum and tunneling motion in difluoromethane–krypton
MARIS, ASSIMO;MELANDRI, SONIA;CAMINATI, WALTHER;ROSSI, IVAN
2005
Abstract
The free-jet millimeter-wave absorption spectra of four isotopomers of difluoromethane krypton have been assigned. The krypton is in the HCH plane of difluoromethane, 3.616 (3) A ˚ from from its center of mass, and forms an angle of 64 (2) with the FCF plane. Ab initio and distributed polarizability model calculations confirm the observed conformation. The measured transitions are split into two component lines due to the tunnelling between two equivalent positions, with Kr above or below the FCF plane. The vibrational splitting, 79.19 (4) MHz, has been used to estimate the inversion barrier (1.23 (5) kJ mol1), while an estimate of the dissociation energy (1.9 kJ mol1) has been deduced from centrifugal distortion effects.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
