Glass formation and thermodynamics of supercooled monatomic liquids.
Glass formation and thermodynamics of supercooled monatomic liquids.
复制标题
过冷单原子液体的玻璃形成和热力学。
DOI：
10.1021/jp111086e
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
T. Odagaki
中科院分区：
文献类型：
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作者：
V. V. Hoang;T. Odagaki
用分子动力学方法研究了具有Lennard-Jones-Gauss（LJG）原子间作用势的过冷简单单原子液体玻璃形成的原子机制。过冷和玻璃态通过从熔体冷却获得。在低温下获得的玻璃态退火很长时间，微秒的顺序，我们发现，玻璃态保持不变，并实现了一个简单的单原子系统在三维的长寿命玻璃态。我们分析了由类林德曼冻结判据定义的类固体和类液体原子的时空性质。分布在整个液体中的固体状原子的数量随着朝向玻璃化转变的温度降低而增加，并且它们形成簇。在深过冷区，几乎所有的类固体原子形成一个单一的渗流集团，其特征尺寸急剧增加进一步冷却。当固体状原子的单个渗滤簇涉及大多数原子以形成相对刚性的固相时，在过冷液体中发生玻璃形成。我们还得到了系统的一些物理量，包括质量密度的温度依赖性，Lindemann比，非相干中间散射函数，α-弛豫时间，径向分布函数的演化，以及Honeycut Andersen分析检测到的局域键对级.我们确定了三个特征温度相关的玻璃化：从液体到固体的动力学交叉冷却时发生的温度，玻璃化转变温度，和Vogel-Fulcher-Tammann温度。对类液原子在玻璃态的行为进行了分析和讨论。
Atomic mechanism of glass formation of a supercooled simple monatomic liquid with Lennard-Jones-Gauss (LJG) interatomic potential is studied by molecular dynamics (MD) simulation. Supercooled and glassy states are obtained by cooling from the melt. Glassy state obtained at low temperatures is annealed for very long time, on the order of microsecond, and we find that glassy state remains unchanged and that the long-lived glassy state of a simple monatomic system in three dimensions is realized. We analyze the spatiotemporal properties of solid-like and liquid-like atoms that are defined by the Lindemann-like freezing criterion. The number of solid-like atoms, distributed throughout the liquid, increases with decreasing temperature toward glass transition and they form clusters. In the deeply supercooled region, almost all solid-like atoms form a single percolation cluster and its characteristic size increases sharply on further cooling. Glass formation in supercooled liquid occurs when a single percolation cluster of solid-like atoms involves a majority of atoms to form a relatively rigid solid phase. We also obtain several physical quantities of the system, including temperature dependence of mass density, Lindemann ratio, incoherent intermediate scattering function, α-relaxation time, evolution of radial distribution function, and local bond-pair orders detected by Honeycutt-Andersen analysis. We identify three characteristic temperatures related to the vitrification: a temperature at which crossover from liquid-like to solid-like dynamics occurs on cooling, the glass transition temperature, and the Vogel-Fulcher-Tammann temperature. Behavior of liquid-like atoms in glassy state has been analyzed and discussed.
影响因子：
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作者：
HONEYCUTT, JD;ANDERSEN, HC
通讯作者：
ANDERSEN, HC