Oliver Warschkow, Edmond P. F. Lee and Timothy G. Wright
The geometries and harmonic vibrational frequencies of BCl2 and BCl2+ have been calculated at various levels of ab initio theory [MP2, MP4(SDQ), CISD and CCSD(T)] and density functional theory (BLYP and B3LYP), using a variety of basis sets. These calculations show the neutral molecule to be bent, with a bond angle of ca. 125°, and the cation to be linear. Calculated vibrational frequencies were compared with experimental values, where available, including isotopic shifts. The ionization energy of the BCl2 molecule was calculated to be 7.33 eV at the Gaussian-2 level of theory; additionally, the heat of formation of the cation was calculated to be 160.4 kcal mol-1. Finally, CIS and MRDCI calculations were performed, in order to ascertain the position of excited electronic states for both the cation and the neutral molecule; the calculated excitation energies were then compared with reported energies for transitions in these species.