A REFINED MONTE-CARLO STUDY OF AQUEOUS UREA SOLUTIONS

In a Monte Carlo study several concentrations of urea in water were st udied with a potential that includes polarization and nonadditive effe cts in the intermolecular interaction. Very long runs, 20 X 10(6) step s, were used to assure that equilibrium was attained. The results obta ined reproduce experimental data, in particular the nitrogen and hydro gen centered radial distribution functions, validating the model and a lso allowing for the assignment of the structure of this function. We can also address the phenomena of the dimerization of urea and the ure a water correlation. Energetic and structural analysis show that there is a urea network which has a particular effect on water structure.