Molecular orbital studies of methanol polymers using a minimal basis set

Abstract

Ab initio minimal basis set LCAO–SCF molecular orbital calculations have been carried out to determine the binding energies and structures of small groups of methanol molecules [(CH₃OH)_n n = 3,4,5,6] with particular emphasis on aspects relevant to experimental measurements on methanol vapor. Cyclic structures are found to be more stable than the open structures for the trimer and higher polymers. The methanol polymers are very similar to the previously studied water polymers in binding energy and structure. A special stability found for the tetramer in infrared, PVT, heat capacity, and thermal conductivity measurements is consistent with the theoretical results.