We compare different quantum-mechanical (QM) periodic models of ordinary ice with the objective to provide reference data for use in simulation studies. Four crystalline structures are considered derived from a cubic or hexagonal arrangement of the oxygen sublattice, both polar and apolar, and three Hamiltonians: HF, PW91 and B3LYP. Two periodic programs have been used, Crystal and Vasp. For each given QM method, the four structures are almost indistinguishable as far as energy and local bonding structure are concerned. Results are much more dependent on the QM technique concerning relative distances and activation barriers.

Proton ordered cubic and hexagonal periodic models of ordinary Ice

CASASSA, Silvia Maria;PISANI, Cesare;
2005-01-01

Abstract

We compare different quantum-mechanical (QM) periodic models of ordinary ice with the objective to provide reference data for use in simulation studies. Four crystalline structures are considered derived from a cubic or hexagonal arrangement of the oxygen sublattice, both polar and apolar, and three Hamiltonians: HF, PW91 and B3LYP. Two periodic programs have been used, Crystal and Vasp. For each given QM method, the four structures are almost indistinguishable as far as energy and local bonding structure are concerned. Results are much more dependent on the QM technique concerning relative distances and activation barriers.
2005
409
110
117
Ice crystal; theoretical model; ab initio calcultations
S. Casassa; M . Calatayud; K. Doll; C. Pisani; C. Minot
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/60878
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 47
  • ???jsp.display-item.citation.isi??? 47
social impact