Dissociation energy and excited-state properties of diatomic Sn₂

Laser vaporization of metallic tin is used to generate Sn₂ molecules in effusive and supersonic expansions. Laser-induced fluorescence studies using isotopic samples of ¹²⁰Sn established the correct vibrational numbering in the excited F 0_u⁺ and determined the Sn₂ molecular constants. From the convergence limit of the upper state the Sn₂ dissociation energy was determined to be 15 330 ± 25 cm^-1, in good agreement with recent ab initio theoretical predictions.