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Anomalies of Water Molecules with Fewer than Four Neighbors

已有 2164 次阅读 2013-7-4 12:35 |个人分类:水之魂|系统分类:论文交流

 

核心提示氢键(O:H-O)的库伦耦合、非对称双振子和弛豫子模型:

主从分段、比热差异、库伦斥力、超短程作用、非对称弛豫、局域双重极化等特性决定冰和水的反常物性。

 

水分子的极性共价键(H-O)在其近邻数目降低时发生自发收缩和强化,同时,近邻氧原子的电子对之间的库伦排斥使范德瓦尔斯键(O:H)极化并大量伸长。

 

水分子自身体积减小但分子间的间距增大。

 

强键的能量决定冰的熔点、高频声子频率、和深层电子能级偏移。

 

常温下水分子团簇、超薄水膜、和水表层的高频声子和氧的芯能级蓝移、强极化、疏水、类冰、和低密度等超固态特性。

 

Journal of Physical Chemistry Letters, 4, 2565-70, July 3, 2013
http://pubs.acs.org/doi/abs/10.1021/jz401029z

 JPCL-water cluster.pdf

 Supporting info.docx

Live Slide: http://pubs.acs.org.ezlibproxy1.ntu.edu.sg/iapps/liveslides/pages/index.htm?mscNo=jz401029z

 

 

Abstract:

Goldschmidt-Pauling contraction of the H-O polar-covalent bond elongates and polarizes the other non-covalent part of the hydrogen bond (O:H-O), i.e. the O:H van der Waals bond, significantly, through the Coulomb repulsion between the electron pairs of adjacent oxygen (O--O). This process enlarges and stiffens those H2O molecules having fewer-than-four neighbors such as molecular clusters, hydration shells, and the surface skin of water in liquid state. The shortening of the H-O bond raises the local density of bonding electrons, which in turn polarizes the lone pairs of electrons on oxygen. The stiffening of the shortened H-O bond increases the magnitude of the O1s binding energy shift, causes the blueshift of the H-O phonon frequencies, and elevates the melting point of molecular clusters and ultrathin films of water, which gives rise to their elastic, hydrophobic, ice-like, and low-density behavior at room temperature.

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