Photoelectron spectroscopy of PbS

The photoelectron spectrum of the gas phase diatomic anion, PbS has been recorded with 2.540 eV photons. Transitions from the X2P PbS anion ground state to the X1R neutral PbS ground state are observed and as-signed. The adiabatic electron affinity of PbS was determined to be 8461 cm1 (1.049 eV). From this value and an energetic cycle, the dissociation energy of PbS dissociating into the ground states of Pb and S was found to be 55.4 kcal/mole (2.40 eV). From a Franck–Condon analysis of the spectrum, the anions bond length, vibrational frequency, and anharmonicity constant were determined to be re 2:390 A, xe 367 cm1, xeve 2:2 cm1, re-spectively