title: Hydrogen bonds and van der waals forces in ice at ambient and high pressures.
abstract: The first principles methods, density-functional theory and quantum Monte Carlo, have been used to examine the balance between van der Waals (vdW) forces and hydrogen bonding in ambient and high-pressure phases of ice. At higher pressure, the contribution to the lattice energy from vdW increases and that from hydrogen bonding decreases, leading vdW to have a substantial effect on the transition pressures between the crystalline ice phases. An important consequence, likely to be of relevance to molecular crystals in general, is that transition pressures obtained from density-functional theory exchange-correlation functionals which neglect vdW forces are greatly overestimated.
authors: Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
authors: Biswajit
authors: B
authors: Santra
authors: Jiří
authors: J
authors: Klimeš
authors: Dario
authors: D
authors: Alfè
authors: Alexandre
authors: A
authors: Tkatchenko
authors: Ben
authors: B
authors: Slater
authors: Angelos
authors: A
authors: Michaelides
authors: Roberto
authors: R
authors: Car
authors: Matthias
authors: M
authors: Scheffler
mesh_terms: D006860:Hydrogen Bonding; D007053:Ice; D008956:Models, Chemical; D009010:Monte Carlo Method; D011312:Pressure; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D007053:Ice