On the Debye-Waller factor of hexagonal ice: a computer simulation study.

摘要: We investigate by molecular dynamics (MD) simulations the temperature dependence of Debye−Waller (DW) factor hexagonal ice with 25 different proton-disordered configurations. Each initial configuration is composed 288 water molecules no net dipole moment. The intermolecular interaction described TIP4P potential. production run simulation 15 ns or longer. observe a change in slope DW around 200 K, which cannot be explained within framework either classical quantum harmonic approximation. Configurations generated MD are subjected to steepest descent energy minimization. Analysis local minimum structures reveals that above K jump other lattice sites via some contain sitting on locations than sites. As time evolves, these defect move back and forth yielding defect-free stru...