Ab initio molecular analysis of dimethyl ether dimer. Thermodynamic properties

Abstract.

 The potential surface of dimethyl ether dimer was subjected to an ab initio study at the second-order Møller–Plesset/6-31+G** level. The initial configurations used in the optimizations were chosen on the basis of a chemical criterion or compiled from the literature. Five different minima were identified and were confirmed by frequency calculations. Accurate characterization of the potential surface of the dimer entails considering electron correlation as several minima that are not exposed by Hartree–Fock/6-31+G** computations. Also, various thermodynamic properties of the minima were determined from their harmonic frequencies.