title: On the representation of many-body interactions in water.
abstract: Recent work has shown that the many-body expansion of the interaction energy can be used to develop analytical representations of global potential energy surfaces (PESs) for water. In this study, the role of short- and long-range interactions at different orders is investigated by analyzing water potentials that treat the leading terms of the many-body expansion through implicit (i.e., TTM3-F and TTM4-F PESs) and explicit (i.e., WHBB and MB-pol PESs) representations. It is found that explicit short-range representations of 2-body and 3-body interactions along with a physically correct incorporation of short- and long-range contributions are necessary for an accurate representation of the water interactions from the gas to the condensed phase. Similarly, a complete many-body representation of the dipole moment surface is found to be crucial to reproducing the correct intensities of the infrared spectrum of liquid water.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA.
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Medders
authors.affiliation: San Diego Supercomputer Center, University of California, San Diego, La Jolla, California 92093, USA.
authors.forename: Andreas W
authors.initials: AW
authors.lastname: Götz
authors.affiliation: Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Morales
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA.
authors.forename: Pushp
authors.initials: P
authors.lastname: Bajaj
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA.
authors.forename: Francesco
authors.initials: F
authors.lastname: Paesani