Thumbnail
Access Restriction
Open

Author Mallory, Joel D. ♦ Mandelshtam, Vladimir A.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY ♦ BINDING ENERGY ♦ CORRELATION FUNCTIONS ♦ DIFFUSION ♦ GROUND STATES ♦ HEAVY WATER ♦ MONTE CARLO METHOD ♦ POTENTIAL ENERGY
Abstract We employ the diffusion Monte Carlo (DMC) method in conjunction with the recently developed, ab initio-based MB-pol potential energy surface to characterize the ground states of small (H{sub 2}O){sub 2−6} clusters and their deuterated isotopomers. Observables, other than the ground state energies, are computed using the descendant weighting approach. Among those are various spatial correlation functions and relative isomer fractions. Interestingly, the ground states of all clusters considered in this study, except for the dimer, are delocalized over at least two conformations that differ by the orientation of one or more water monomers with the relative isomer populations being sensitive to the isotope substitution. Most remarkably, the ground state of the (H{sub 2}O){sub 6} hexamer is represented by four distinct cage structures, while that of (D{sub 2}O){sub 6} is dominated by the prism, i.e., the global minimum geometry, with a very small contribution from a prism-book geometry. In addition, for (H{sub 2}O){sub 6} and (D{sub 2}O){sub 6}, we performed DMC calculations to compute the ground states constrained to the cage and prism geometries. These calculations compared results for three different potentials, MB-pol, TTM3/F, and q-TIP4P/F.
ISSN 00219606
Educational Use Research
Learning Resource Type Article
Publisher Date 2016-08-14
Publisher Place United States
Journal Journal of Chemical Physics
Volume Number 145
Issue Number 6


Open content in new tab

   Open content in new tab