Theoretical study of the potential energy surface of diglyme

The potential energy surface of diglyme has been investigated using ab initio molecular orbital theory. The all-trans conformer and 20 conformers having either one- or two-gauche conformations around C-C or C-O bonds were studied at the HF/6-31G(d) level, The four lowest energy structures were further investigated with larger basis sets and with inclusion of correlation effects. At the highest level of theory, the tg(+)g(-)t(3) conformer is 0.1 kcal/mol more stable than the all-trans conformer, while the tgt(4) and g(+)g(-)t(4) conformers are slightly less stable than the all-trans conformer.