The molecular electronic structure of the lowest 1Σ+g, 3Σ+u, 1Σ+u, 3Σ+g, 1Πu, 1Πg, 3Πu, and 3Πg states of Na2

Abstract
The multiconfiguration self‐consistent field wave functions and potential energy curves for the lowest lying 1Σ+g, 1Σ+u, 3Σ+g, 3Σ+u, 1Πg, 1Πu, 3Πg, and 3Πu states of Na2 are reported. We find good agreement with recent experimental estimates of the dissociation energies for the 1Σ+g and 1Σ+u states. We find the long range hump in the B 1Πu curve to have its maximum height of 520 cm−1 above the separated atom asymptote at R=6.45±0.1 Å; recent experimental estimates of the height are 474 and 554±120 cm−1.