Correlated Gaussian wavefunctions for H3+

Quantum chemical calculations have been performed on H3+ using correlated Gaussian wavefunctions of a type suggested by Singer. The resulting upper bound energy, E = −1.34335 a.u., is lower than all previous results except those of Conroy. Vibrational frequencies were calculated to be ω1 = 3272 cm−1 (symmetrical stretch) and ω2 = 2735 cm−1 (bending mode). The kinetic energy, nuclear repulsion energy, interelectronic repulsion energy, nuclear-electronic attraction energy, virial, and squared electronic position expectation values were computed.