Calculation of Structural and Dynamical Properties of Complex Materials by Car-Parrinello ab initio Molecular Dynamics Simulations

给定几何形状，即使是非常复杂的材料，也可以在局部密度近似下计算电子结构。然而，非常复杂的材料或无序系统的几何结构往往是未知的。Car-Parrinello的从头分子动力学刺激方法使实现非常复杂材料的结构和动力学性质的第一性原理预测迈出了重要的一步。虽然这种方法在超级计算机上实现时允许模拟许多更重要的有趣问题，但仍然很大。另一方面，考虑到机器的大规模并行处理器架构的出现。Car-Parrinello仿真在连接机上的初步测试表明，它可以很好地映射到并行架构上。只要该代码针对连接机进行了充分优化，就有可能从第一性原理来预测复杂材料的结构和动态特性。例子包括模拟表面氧化，分子/团簇与表面的相互作用，从头开始研究扫描隧道显微镜和原子力显微镜图像。

Given a geometry, electronic structure may be calculated for even very complex materials within the local density approximation. However, geometrical sturctures of very complex materials or disordered systems are often not known. A major step toward the achievement of first principle predictions of the structural and dynamical properties of very complex materials has been made possible by the Car-Parrinello method of ab intio molecular dynmics stimulation. While this approach when implemented on supercomputers allows the simulation of many interesting problems of even more importance are still to large. On the otherhand, the appearance of the massively parallel processor architecture of the machine is taken into account. Preliminary testing of Car-Parrinello simulation on the Connection Machine indicates that it maps well onto parallel architectures. Provided that the code is fully optimized for the Connection Machine it will be possible to predict strutural and dynamical properties of complex materials form first principles. Examples would include simulation of surface oxidation, molecular/cluster interaction with surfaces and ab initio studies of scanning tunnel microscope and atom force microscope images.