Molecular polarization in water chains

Molecular dipole moments, charges, and difference electron densities have been calculated from Hartree-Fock calculations for each individual

molecule along geometry-optimized water chains with

n=1,...,12,infinity. The complementarity of the three properties is

discussed. Although yielding rather different aspects of the

polarization they all show that the polarization converges much faster

for the molecules at the ends of the chains compared to the middle.

Moreover, the middle molecules in the long chains acquire an induced

dipole moment about twice as large as those at the ends. An electron

charge transfer along the chains leaves only the central water

molecules neutral, and creates an additional contribution to the net

system dipole, a phenomenon which should arise also in small real

finite clusters and chains. (C) 1999 American Institute of Physics.

[S0021-9606(99)51324-X].