The Infra-Red Absorption by Hydrogen Selenide, Deuterium Selenide and Deutero-Hydrogen Selenide

Abstract

The infra‐red spectra of H₂Se, D₂Se and HDSe have been measured and the positions of the three fundamental frequencies for each molecule have been determined. These are; for H₂Se v₁ = 2260 cm^—1, v₂ = 1074 cm^—1, v₃ = 2350 cm^—1; for D₂Se, v₁ = 1630 cm^—1, v₂ = 745 cm^—1, v₃ = 1696 cm^—1; for HDSe, v₁ = 1691 cm^—1, v₂ = 905 cm^—1 and v₃ = 2352 cm^—1. Interpretation of the observed data has led to the adoption of an obtuse model where the H–Se–H bond angle is slightly in excess of 90°. The H–Se distances are evaluated to be 1.6A and the H–H distance is equal to 2.3A. The product relations of Redlich are made use of as a verification of a correct assignment of frequencies and for a correct determination of the band centers.