Ab Initio Studies of Radicals HBX (X=H, F, Cl, Br): Molecular Structure, Vibrational Frequencies and Potential Energy

We describe high-level ab initio calculations on the BH_2, HBF, HBCl and HBBr radicals. Molecular structure, vibrational frequencies and potential energy curves of the ground state and the first excited state, which are two Renner–Teller components for a ^2\it \Pi state at linearity, are studied using the basis sets aug-cc-pVTZ and icMRCI+Q technique. On the basis of the potential energy curves, a reliable potential energy barrier to dissociation HB+X (X=F, Cl, Br) fragments and to linearity are given. The ab initio results will add some understanding on the spectrum and the photo-dissociation dynamics of the series of radicals.