Journal of Physical Chemistry A, Vol.104, No.6, 1271-1277, 2000
The potential energy surface and re-vibrational states of He-CH+
The potential energy surface (PES) for the interaction of He with CH+ (X(1)Sigma(+)) has been determined using nb initio CCSD(T) calculations. The resulting PES has a T-shaped minimum energy structure and a well depth of 477 cm(-1). Re-vibrational calculations are performed to assess spectroscopic observables which should aid the experimental detection of this as yet unobserved system. Using an adiabatic correction scheme the influence of exciting the intermolecular (CH+) stretching vibration is examined. For the electronic ground state no appreciable red shift of the monomer frequency is found in contrast to previously investigated systems of the same type. Exploratory calculations of the interaction between CHf (a(3)Pi) and He are presented in view of the ongoing interest in CH+ in astrophysical environments, The (3)A," component has a deep T-shaped minimum energy structure with a well of about 900 cm(-1). Conversely, the (3)A' PES is comparatively isotropic with a linear geometry and a well of roughly 300 cm(-1).
Keywords:CORRELATED MOLECULAR CALCULATIONS;INFRARED PREDISSOCIATIONSPECTRA;GAUSSIAN-BASIS SETS;MIDINFRARED SPECTRA;IONICCOMPLEXES;OH+-HE;SPECTROSCOPY;CLUSTERS;AR;DYNAMICS