手段。泰森多边形指数常用
第一近邻的配位数也是一种传统的分析微观结构的方式，此概念首先由阿尔弗雷德·维尔纳提出，原来更多地用于化学结构的表征，是配位化学的基础。在微观结构的表征中，配位数是用来描述中心原子第一壳层内原子的平均数目，反映的是中心原子与其它原子的结合能力和配位关系，描述的是体系中粒子排列的紧密程度，配位数越大，粒子排列越紧密。一般来说配位数是通过对径向分布函数的第一峰进行积分来得到。对于Voronoi指数分析而言，由于泰森多边形的算法就是计算中心原子与配位原子之间的连线平分面，因此，通过对Voronoi指数的累加，也能得到中心原子的配位数。对于晶体结构，通过配位数可以判断出晶体的结构；对于液态的非晶态结构，配位数可以作为一个发生结构转变的敏感参量，为结构转变的判断提供依据。例如，对于液体中发生的液?液相变现象，众多研究[39]都将配位数的变化作为判断的依据之一。
4展望
如果分子体系足够小，我们又有足够的耐心，即便只使用为数不多的处理器，完成微秒甚至是毫秒级时间尺度的模拟已不成问题，几年前就已经实现。然而，只有大规模并行架构，特别是千兆级运算速度的超级计算机的出现, 我们才得以处理数百万个原子组成的分子体系。但现阶段，毫秒级时间尺度或者百万原子空间尺度的分子模拟仍然构成技术上的巨大挑战，这恰恰又昭示着一个新时代的来临。随着第一台千兆级浮点运算速度的超级计算机投入使用，科学家已经开始期待着亿亿级计算机的到来并开始考虑这种新型架构将能够处理的分子体系的种类。
假使在未来的几十年，分子动力学的发展仍然紧跟摩尔定律所预测的计算机发展趋势，van Gunsteren[40]乐观地预测，未来20年内，我们将可以在纳秒级时间尺度上模拟一个完整的细菌，如大肠杆菌，大约20年后，可以模拟一个完整的哺乳动物细胞。这些基于目前硬件性能和软件发展水平所作出的推测固然很振奋人心，但我们应该清楚地认识到横亘在模拟时间尺度和空间尺度之间的鸿沟依然难以逾越。在未来的计算机模拟中，利用直接无偏分子动力学模拟研究生物大体系，有可能提供时间相关和动力学相关信息。而实现这一目标，我们仍然还有很长的路要走。
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