Microsolvation effect on alanine: a many-body interaction study using ab initio method

Abstract

The interaction between alanine and three water molecules is studied using ab initio method and 6-311+G* basis set. Various structures for alanine–(water) 3 complex are investigated. Four different lowest energy structures are reported. Many-body analysis is also carried out to obtain relaxation energy and many-body energies (two, three and four-body). Out of the four conformers, the most stable conformer has basis set superposition error corrected total energy −550.0962701 hartree and binding energy −38.04 kcal/mol. Many-body analysis shows that two and three-body interaction energies have significant contribution to the binding energies, whereas four-body interaction energies are negligible as compared to two and three-body interaction energies.