Ab initio calculations of the electronic states of AsH2 including dissociation characteristics

作者：Alekseyev Aleksey B^*; Buenker Robert J; Liebermann Heinz Peter

来源：Journal of Chemical Physics, 2011, 135(24): 244303.

DOI：10.1063/1.3671374

Multireference configuration interaction calculations have been carried out for low-lying electronic states of AsH2. Bending potentials for the ten lowest states of AsH2 are obtained in C-2v symmetry for As-H distances fixed at the the ground state equilibrium value of 2.845 a(0), as well as for the minimum energy path constrained to R-1 = R-2. The calculated equilibrium geometries for the (X) over tilde B-2(1) ground state and the (A) over tilde (2)A(1) excited state agree very well with the previous experimental and theoretical results, whereas the data for the higher-lying states are obtained for the first time. Asymmetric potential energy surface (PES) cuts (at R-1 = 2.845 a(0), theta = 90.7 degrees) and two-dimensional (2D) PESs for the lowest three states are also new. The calculated ab initio data are used for analysis of possible AsH2 photodissociation channels and predissociation effects. It is shown that the (A) over tilde (2)A(1) - (X) over tilde B-2(1) transition dipole moment decreases with increasing bending angle, which influences the intensity distribution in the (A) over tilde (0, 0, 0) -> (X) over tilde emission spectrum (v(2)'' bending series), shifting its maximum to smaller v(2)'' quantum numbers.

• 出版日期2011-12-28