HSbXH (X = N, P, As, Sb, and Bi) isomers in the singlet and triplet states. A theoretical study

The lowest singlet and triplet potential energy surfaces for all group 15 HSbXH (X = N, P, As, Sb, and Bi) systems have been explored through ab initio calculations. The geometries of the various isomers were determined at the QCISD/LANL2DZdp level and confirmed to be minima by vibrational analysis. Our model calculations indicate that the relativistic effect on heavier group 15 elements should play an important role in determining the geometries as well as the stability of HSbXH molecules. The results obtained are in good agreement with the available experimental data and allow a number of predictions to be made.