On the structure of HBPH

High level ab initio calculations have been used to study isomers of HBPH. HB = PH and BPH2 were found to be local minima, the former appearing to be the global minimum and over 40 kcal mol−1 more stable than the latter. HB = PH has a cis, planar structure with an essentially linear HBP unit, and the second H bridges the B and P. There is no local minimum corresponding to H2BP. Qualitative differences between SCF and correlated potential energy surfaces are observed.