Molecular valence calculations on cyclohexasulfur, cycloheptasulfur, and cyclooctasulfur

Abstract

Abstract A theoretical study of homocyclic sulfur species S 6 , S 7 , and S 8 was carried out using a molecular valence method involving stepwise approximations for orthogonality and core‐valence interactions. The valence shell orbitals are described at the minimal basis level. The geometries of the molecules are predicted well as compared with other theoretical studies and the experimental values. The slight overestimation of the SS bond length is typical to the nonpolarized basis sets. The energies of the valence orbitals are well in accord with the conventional all‐electron ab initio results. The trend in the stabilities of the three molecules is discussed. The present method provides an attractive possibility to study homocyclic and heterocyclic systems involving heavier chalcogens with no increase of the computing time.