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arXiv 0901.4273cond-mat.soft
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一个新的水异常:质子平均动能的温度依赖性

A new water anomaly: the temperature dependence of the proton mean kinetic energy

Davide Flammini, Fabio Bruni, Maria Antonietta Ricci

摘要:

水中质子的平均动能由深度非弹性中子散射实验确定,该实验在最大密度温度以上和以下以及在过冷相中进行。这种能量的温度依赖性显示出异常的行为,因为它发生在许多水的性质。特别是两个区域的最大动能被确定:第一个,在过冷阶段的范围内269 K - 272 K,和第二个以上273 K。在这两个区域中,测量的质子动能都超过了基于半经典模型的理论预测。值得注意的是,质子平均动能在277 K处具有最大值,这是水的最大密度的温度。在过冷亚稳相,测量的平均动能和质子动量分布清楚地表明质子离域之间的两个H-键合的氧。

英文摘要:

The mean kinetic energy of protons in water is determined by Deep Inelastic Neutron Scattering experiments, performed above and below the temperature of maximum density and in the supercooled phase. The temperature dependence of this energy shows an anomalous behavior, as it occurs for many water properties. In particular two regions of maximum kinetic energy are identified: the first one, in the supercooled phase in the range 269 K - 272 K, and a second one above 273 K. In both these regions the measured proton kinetic energy exceedes the theoretical prediction based on a semi-classical model. Noteworthy, the proton mean kinetic energy has a maximum at 277 K, the temperature of the maximum density of water. In the supercooled metastable phase the measured mean kinetic energy and the proton momentum distribution clearly indicate proton delocalization between two H-bonded oxygens.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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