Theoretical study for the structures of the CH3NH2, CH3NH2/HF and other related clusters

Abstract

The study of intermolecular interactions is a useful step toward gaining a basic understanding of the dynamic behaviour of molecules in various environments. Especially, interactions of the metylamine (CH3NH2) molecule with other molecules provide valuable information on protein-protein interactions or protein-solvent interactions in biological systems. From this point of view, high-level ab initio calculations [MP2] using correlation consistent basis sets of Dunning [aug-cc-pVTZ] were carried out to study the structures and stability of CH3NH2/H2O, CH3NH2/HF, and other clusters related to CH3NH2 derivatives. For CH3NH2/H2O, several different orientations were studied. From the result of full optimization, the bond angle N(CH3NH2) .H(H2O)-O(H2O) is 162 in the most stable structure of CH3NH2/H2O. Furthermore, for CH3NH2/HF, N(CH3NH2) .H(HF)-F(HF) is linear(180 ). The details of the portential energy surfaces and the effects of the basis set superposion error (BSSE) have been discussed. In the case of other clusters related to CH3NH2 derivatives (especially CH3NH2 dimer, trimer, etc) further investigations have been in progress.