Computational and vibrational spectroscopy study of the microclusters of C2 symmetry urea molecule in the 1A electronic ground state

Abstract

A series of microclusters containing up to eigtht C 2 symmetry urea molecules was studied at the B3LYP density functional theory level. The equilibrium structures of each aggregate and the respective theoretical infrared spectra were determined from B3LYP/6-311++G** calculations. Relative stability considerations and binding energy of each species were obtained from MP2/6-311++G**//B3LYP/6-311++G** single point calculations, including basis set superposition error (BSSE) and zero-point energy (ZPE) corrections. Further single point energy calculations at the MP2/6-311++G(3df,3pd)//B3LYP/6-311++G** level were made for all dimers and trimers. The theoretical study of these aggregates was integrated with FT-IR spectroscopy measurements in low temperature argon matrixes.