The Electronic Structure of the Ground State of the HeH⁺ Molecule

Abstract

The total electronic energy of HeH⁺ is calculated with the wave functions in which the “in-out correlation” is included by using two different 1s Slater type atomic orbitals of He. The conclusion is that the effect of the in-out correlation of electrons in the vicinity of the He nucleus is considerable in HeH⁺, though it is somewhat smaller than that in the He atom. Among the four wave functions employed here, the simplest one can give the qualitative explanation of the electronic structure of this system. The results computed with the simplest wave function are E(R_e)=−2.935026999 a.u., R_e=1.46663 a.u. ω_e=3.1×10³ cm⁻¹ and D_e=1.62 eV. The best values of E(R_e) and R_e, calculated by use of the most flexible wave function, amount to −2.93819775 a.u. and 1.4648 a.u., respectively.