REACTIONS OF SELENIUM AND OXYGEN - MATRIX INFRARED-SPECTRA AND DENSITY-FUNCTIONAL CALCULATIONS OF NOVEL SEXOY MOLECULES

Reactions of selenium and oxygen were performed using five different m ethods, and the products were trapped for matrix infrared spectroscopi c study. Based on different chemistry, photolysis and annealing behavi or, selenium and oxygen isotopic substitution, and DFT structure and f requency calculations, several new selenium oxides are characterized. In addition to SeO, SeO2, and SeO3, and the (Se-2)(O-2) complex, the n ew molecules SeSeO, SeOO, Se2O2, and OSeOO are identified. Several iso mers of Se2O2 are accidentally almost degenerate; the species identifi ed, which contains a three-membered ring with an exocyclic Se=O unit, is one of the most stable. The OSeOO species is probably a planar cis chain isomer (C-s symmetry), which is calculated to lie about 100 kJ/m ol above the D-3h structure of SeO3.