Ab initio studies of structural features not easily amenable to experiment: Part 31. Conformational analysis and molecular structures of ethylene glycol

Abstract The geometries of ten conformations of ethylene glycol have been refined without any geometrical constraints by the ab initio gradient method on the 4-21G level. The two most stable forms found are tGg′ and gGg′ , both of which are stabilized by internal hydrogen bonding. A number of conformationally dependent structural trends are apparent in the optimized local geometries. Bond distances and bond angles in different conformations can vary by up to 0.01–0.02 A and 5°, respectively. The results are found to be consistent with most of the previous investigations of the system.