Applications of Diatomics-in-Molecules Theory. II. Prediction of a Stable Li3 Molecule

Abstract

Diatomics‐in‐molecules theory applied to the Li₃ molecule leads to the prediction of two forms stable with respect to ${\mathrm{Li}}_2{(}^1{\Sigma }_g^{+}\mathrm{)\hspace{0.17em}+\hspace{0.17em}}\mathrm{Li}{(}^2\mathrm{S)}$ : a bent ${}^2{A}_1$ state with an atomization energy at 0°K of 32.74 kcal/mole and an ionization energy of about 111 kcal/mole; a strongly bent ${}^2{B}_2$ state with an atomization energy at 0°K of 30.34 kcal/mole. Potential‐energy surfaces and fundamental vibrational frequencies are predicted for both states. Characteristics of the less stable linear conformation are discussed and compared with H₃.