| Autor: |
Stern, Harry A., Rittner, F., Berne, B. J., Friesner, Richard A. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; Aug2001, Vol. 115 Issue 5, p2237, 15p, 5 Diagrams, 9 Charts, 15 Graphs |
| Abstrakt: |
We present a general formalism for polarizable electrostatics based on fluctuating bond-charge increments and polarizable dipoles and its application to a five-site model for water. The parametrization is based largely on quantum-chemical calculations and should be easily transferable to other molecules. To examine basis-set effects we parametrized two models from two sets of quantum calculations, using the aug-cc-pVTZ and aug-cc-pVQZ basis sets. We computed several gas-phase and condensed-phase properties and compared with experiment or ab initio calculations as available. The models are quite similar and give condensed-phase properties at ambient conditions that are in reasonable accord with experiment, but evince errors consistent with a liquid-state dipole moment that is slightly too large. The model fit to the aug-cc-pVTZ basis set has a smaller liquid-phase dipole moment and thus gives a somewhat better description of liquid water at ambient conditions. This model also performs well away from room temperature, deviating less than 2% from the experimental density from 0 to 100 °C, and showing good agreement with experimental radial distribution functions, although the temperature of maximum density (∼20 °C) is slightly too high and the model somewhat underpredicts the persistence of the hydrogen-bond network at elevated temperatures. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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