The total energy of HeH was computed using a method of molecular orbital calculation in which the total wavefunction is taken as a linear combination of configurations, each a properly antisymmetrized product of flexible one‐electron functions in an elliptic coordinate system. We have examined the lowest 2Π state of this system and both of the 2Σ excited states which arise from the interaction of ground‐state He and a 2p or 2s H atom. The lowest 2Π state of HeH and the first excited 2Σ state are found to be bonding with calculated dissociation energies of 1.935 and 2.336 eV, respectively. A comparison of these results with those previously reported for the ground state of HeH and the molecular ion HeH+ indicates that the charge distribution about the helium atom is similar in all of these systems and it is predicted that, with the single exception of the ground state, all of the doublet states of HeH up to the ionization limit of the H atom are bonding and can be represented by very similar potential energy curves.

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© 1963 American Institute of Physics.
1963
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