Basis‐set optimization for first‐principles simulation of liquid water

Abstract

AbstractWe describe simulation results for the structure and dynamics of liquid water using the SIESTA electronic structure approach. We find that the structure of water depends strongly on the particular basis set used. Applying a systematic approach to varying the basis set, we find that the basis set that results in good agreement with experimental binding energies for isolated water dimers also provides a reasonable description of the radial distribution functions of liquid water. We show that the structure of liquid water varies in a systematic fashion with the choice of basis set. Comparable to many other first‐principles studies of liquid water using gradient‐corrected density functionals, the liquid is somewhat overstructured. The possibility of further improvements through a better choice of the basis set is discussed. While improvements are likely, application to large‐scale systems will require use of a computational algorithm whose computational cost scales linearly with system size. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007