TY - JOUR

T1 - Local structure and work of formation of water clusters studied by molecular dynamics simulations

AU - Brodskaya, Elena N.

AU - Eriksson, Jan Christer

AU - Laaksonen, Aatto

AU - Rusanov, Anatoly I.

PY - 1996/6/1

Y1 - 1996/6/1

N2 - Small clusters composed of 64, 94, 125, 190, 256, and 512 water molecules have been studied by molecular dynamics simulations using the ST2 water model. Radial profiles of the local density, energy, electric potential, and components of the pressure tensor were calculated. The work of formation was derived for the different cluster sizes on the basis of the normal pressure tensor component P(N) and was related to the curvature-dependent surface tension of the clusters. Our calculations show that the surface tension γ increases with the cluster radius R in the size range investigated, to beyond the limiting value for the flat interface. This course of the γ(R) function is consistent with the corresponding surface energy function which was obtained in a more direct manner from the energetic parameters. In addition, it indicates, however, that the ST2 water model yields surface entropy values which are much lower than anticipated for real water. We have also elucidated the surface effect on the self-diffusion coefficient and on the reorientatonal relaxation time.

AB - Small clusters composed of 64, 94, 125, 190, 256, and 512 water molecules have been studied by molecular dynamics simulations using the ST2 water model. Radial profiles of the local density, energy, electric potential, and components of the pressure tensor were calculated. The work of formation was derived for the different cluster sizes on the basis of the normal pressure tensor component P(N) and was related to the curvature-dependent surface tension of the clusters. Our calculations show that the surface tension γ increases with the cluster radius R in the size range investigated, to beyond the limiting value for the flat interface. This course of the γ(R) function is consistent with the corresponding surface energy function which was obtained in a more direct manner from the energetic parameters. In addition, it indicates, however, that the ST2 water model yields surface entropy values which are much lower than anticipated for real water. We have also elucidated the surface effect on the self-diffusion coefficient and on the reorientatonal relaxation time.

KW - molecular dynamics simulations, of water clusters

KW - pressure tension, in water droplets

KW - surface tension, of water droplets

KW - water clusters

KW - work of formation, of water clusters

UR - http://www.scopus.com/inward/record.url?scp=0029952499&partnerID=8YFLogxK

U2 - 10.1006/jcis.1996.0276

DO - 10.1006/jcis.1996.0276

M3 - Article

AN - SCOPUS:0029952499

VL - 180

SP - 86

EP - 97

JO - Journal of Colloid and Interface Science

JF - Journal of Colloid and Interface Science

SN - 0021-9797

IS - 1

ER -