Monte Carlo simulation study on the conformation and interaction of the glycine zwitterion in aqueous solution

摘要

A Monte Carlo simulation with the statistical perturbation method has been employed to determine the relative stabilities imong four representative conformations of the glycine .witterion (GLYZ) in aqueous solution. The (θ,δ) = (O,O) and (60,0) Conformations, in which the dihedral angle 0 between the NCC and CCO planes is 0°, were found to be more stable than the 0,90) and (60,90) conformations, in which 0=90°. The relative stabilities of these four conformations are well elucidated on the asis of solvent-solute interactions using two-dimensional radial distribution functions. Ah initio MO/GB calculations includ-ng the solvent effect via the generalized Bom formula gave similar results for the relative stabilities of the four conformations nsolution.