title: Density, Elasticity, and Stability Anomalies of Water Molecules with Fewer than Four Neighbors.
abstract: Goldschmidt-Pauling contraction of the H-O polar-covalent bond elongates and polarizes the other noncovalent part of the hydrogen bond (O:H-O), that is, 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 skins of water and ice. 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 blue shift 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, highly-polarized, ice-like, and low-density behavior at room temperature.
authors.affiliation: Key Laboratory of Low-Dimensional Materials and Application Technologies and Faculty of Materials and Optoelectronics and Physics, Xiangtan University , Hunan 411105, China.|School of Electrical and Electronic Engineering, Nanyang Technological University , Singapore 639798.
authors.forename: Chang Q
authors.initials: CQ
authors.lastname: Sun
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University , Singapore 639798.|Center for Coordination Bond and Electronic Engineering, College of Materials Science and Engineering, China Jiliang University , Hangzhou 310018, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University , Beijing 100084, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Low-Dimensional Materials and Application Technologies and Faculty of Materials and Optoelectronics and Physics, Xiangtan University , Hunan 411105, China.
authors.forename: Yongli
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Key Laboratory of Low-Dimensional Materials and Application Technologies and Faculty of Materials and Optoelectronics and Physics, Xiangtan University , Hunan 411105, China.
authors.forename: Yichun
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: School of Materials Science, Jilin University , Changchun 130012, China.
authors.forename: Weitao
authors.initials: W
authors.lastname: Zheng
keywords: Raman; XPS; hydration; melting point; polarization; water molecules; water surface