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冰之魂8: <PRL>新证-压致虚键增强实键减弱

已有 2259 次阅读 2011-10-30 00:08 |个人分类:水之魂|系统分类:科普集锦|关键词:冰,高压| 高压

定义:氢键 = O2- :H+/p - O2- ; 

 
":" -电子孤对(虚键); "-" -极性共价键(实键)

下文报道结果证实我们的预言:压致虚键收缩且增强,实键变边长且减弱


原文摘要:
The first principles methods, density-functional theory and quantum Monte Carlo, have been used to examine the balance between van der Waals (vdW) forces [电子孤对] and hydrogen bonding [实键] 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.
 
Biswajit Santra et al., Hydrogen Bonds and van der Waals Forces in Ice at Ambient and High Pressures, Phys. Rev. Lett. 107, 185701 (2011)



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