LiH Potential Curves and Wavefunctions for X 1Σ+, A 1Σ+, B 1Π, 3Σ+, and Π3

Ab initio multiconfiguration self‐consistent‐field calculations are reported for the potential curves and electronic wave functions of the states ${\mathrm{X\hspace{0.17em}}}^1{\Sigma }^{+}{\mathrm{,\; A\hspace{0.17em}}}^1{\Sigma }^{+}{\mathrm{,\; B\hspace{0.17em}}}^1{\mathrm{\Pi ,\hspace{0.17em}}}^3{\Sigma }^{+}$ , and ${}^3\Pi$ of LiH. In this calculation, the outer two electrons are correlated, while the 1σ shell, essentially a K shell on Li, is left uncorrelated. The obtained dissociation energies, with the known experimental values in parentheses, are $D_e{\mathrm{(X\hspace{0.17em}}}^1{\Sigma }^{+}\text{)=2.411(2.5154)\hspace{0.17em}}\mathrm{eV}{\mathrm{,\hspace{0.17em}D}}_e{\mathrm{(A\hspace{0.17em}}}^1{\Sigma }^{+}\text{)=1.048\hspace{0.17em}(1.0765)\hspace{0.17em}}\mathrm{eV}{\mathrm{,\; D}}_e{\mathrm{(B\hspace{0.17em}}}^1\text{Π)=0.017\hspace{0.17em}(0.035)\hspace{0.17em}}\mathrm{eV}$ and $D_e{(}^3\text{Π)=0.226\hspace{0.17em}}\mathrm{eV}$ .