Diffusivity, excess entropy, and the potential-energy landscape of monatomic liquids
Diffusivity, excess entropy, and the potential-energy landscape of monatomic liquids
复制标题
DOI：
10.1063/1.2140282
复制
发表时间：
2006-01-07
影响因子：
4.4
通讯作者：
Chakravarty, C
中科院分区：
文献类型：
--
作者：
Chakraborty, SN;Chakravarty, C
热力学，运输和势能景观功能之间的联系进行了研究，使用微正则分子动力学和等温等压系综Monte Carlo模拟与Lennard-Jones型对相互作用的液体。对单原子Lennard-Jones液体的两种变体进行了瞬时简正模和鞍点分析。扩散系数线性依赖于几个关键属性的瞬时和鞍形配置的能量，负曲率方向的分数，和平均值，最大值和最小特征值的海森。由于Dzugutov标度关系也适用于这样的系统[Nature（伦敦）381，137（1996）]，在两粒子近似中，过量熵的指数显示出与扩散率相同的对能量景观性质的线性依赖性。(c)2006年，美国物理学会。
The connection between thermodynamic, transport, and potential-energy landscape features is studied for liquids with Lennard-Jones-type pair interactions using both microcanonical molecular-dynamics and isothermal-isobaric ensemble Monte Carlo simulations. Instantaneous normal-mode and saddle-point analyses of two variants of the monatomic Lennard-Jones liquid have been performed. The diffusivity is shown to depend linearly on several key properties of instantaneous and saddle configurations-the energy, the fraction of negative curvature directions, and the mean, maximum, and minimum eigenvalues of the Hessian. Since the Dzugutov scaling relationship also holds for such systems [Nature (London) 381, 137 (1996)], the exponential of the excess entropy, within the two-particle approximation, displays the same linear dependence on energy landscape properties as the diffusivity. (c) 2006 American Institute of Physics.