Triatomic Linear Molecules Containing Carbon and Oxygen, Sulfur, Selenium, or Tellurium. II. Potential Constants

Abstract

The fundamental vibrational frequencies for CO₂, CS₂, CSe₂, OCS, OCSe, SCSe, and SCTe have been used in a uniform analysis based on the valence force field to evaluate the force constants. The extensive literature on CO₂, OCS, and CS₂ has been reviewed since a choice of frequencies is necessary due to significant divergence of some earlier data. The stretching interaction constants have been used to test the validity of a theoretical expression for calculating such an interaction. A compilation of the best values of the internuclear distances in this family is also presented. The main stretching force constant and the bond distance for a given bond (e.g., C=O) may be transferred from molecule to molecule to a high degree of approximation. The force constants, in 10⁵ dynes/cm, for the bonds C=O, C=S, C=Se, and C=Te are, respectively: 15.96±0.04, 7.62±0.20, 5.79±0.16, and 4.58. The interaction constants, for the molecules in the same order and the same units are 1.262, 0.661, 0.36, 0.97, 0.85, 0.53, and 0.30.