Abstract
The inclusion of exchange repulsion terms in the explicit polarization (X-Pol) model is examined by antisymmetrizing the X-Pol Hartree product wave function; this yields X-Pol with full eXchange, called X-Pol-X. When the monomers are treated by Hartree-Fock theory, this calculation can be accomplished by using the formalism of block-localized wave functions (BLW) that has been used in a variety of applications. In this case the block-localized structure in the X-Pol-X wave function allows for decomposition of the full Fock matrix of a dimension of M blocks into M smaller Fock matrices. The method is illustrated by considering two trimer structures of water clusters, and it is found that the total exchange repulsion energies in these hydrogen-bonding test cases are adequately treated andsto a good approximationsare pairwise additive. We also present a formalism to yield a simplified Fock matrix by making use of the neglect of interfragment differential overlap (NIDO) approximation, which is less severe than the neglect of diatomic differential overlap (NDDO) approximation.
Original language | English (US) |
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Pages (from-to) | 2469-2476 |
Number of pages | 8 |
Journal | Journal of Chemical Theory and Computation |
Volume | 6 |
Issue number | 8 |
DOIs | |
State | Published - Aug 10 2010 |
Bibliographical note
Publisher Copyright:© 2010 American Chemical Society.