Saika-Voivod Ivan, Sciortino Francesco, Grande Tor, Poole Peter H
Dipartimento di Fisica and Istituto Nazionale per la Fisica della Materia, Università di Roma La Sapienza, Piazzale Aldo Moro 2, 00185 Roma, Italy.
Philos Trans A Math Phys Eng Sci. 2005 Feb 15;363(1827):525-33; discussion 534-5. doi: 10.1098/rsta.2004.1506.
We review how molecular dynamics computer simulations are providing a comprehensive picture of the behaviour of silica, as modelled by the van Beest-Kramer-van Santen (BKS) potential. We have recently evaluated a number of key properties of this model system: the phase diagram, including melting lines of three crystal phases; the equation of state and free energy of the liquid phase; the dynamical equation of state; the average energy of inherent structures, and configurational entropy, associated with the potential energy landscape of the liquid; and a characterization of the local coordination environments in the supercooled liquid. The results reveal the interplay among a number of phenomena, in particular, the relationship between the energy landscape and the fragile-to-strong crossover of the liquid dynamics; and the relation of both of these to the possibility of a liquid-liquid phase transition in the supercooled liquid.
我们回顾了分子动力学计算机模拟如何通过范·贝斯特-克莱默-范·桑滕（BKS）势对二氧化硅行为进行全面建模。我们最近评估了该模型系统的一些关键性质：相图，包括三种晶相的熔点线；液相的状态方程和自由能；动态状态方程；与液相势能面相关的固有结构的平均能量和构型熵；以及过冷液体中局部配位环境的特征。结果揭示了许多现象之间的相互作用，特别是能量景观与液体动力学从脆弱到强烈转变之间的关系；以及这两者与过冷液体中液-液相转变可能性的关系。
