Achieving Chemical Accuracy with Coupled-Cluster Theory
Achieving Chemical Accuracy with Coupled-Cluster Theory
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DOI：
10.1007/978-94-011-0193-6_2
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
Timothy J. Lee;G. Scuseria
中科院分区：
文献类型：
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作者：
Timothy J. Lee;G. Scuseria
由于在过去几年中耦合团簇理论在形式和计算上的进步，现在可以获得非常精确的分子几何形状，振动频率，生成热，结合能和垂直电子激发能。例如，基于大量计算的统计分析，表明CCSD（T）/spdfg理论水平给出的rXH、rXY（双键）和rXY（三键）的平均误差分别为0.0010、0.0020和0.0026 π，理论键距通常相对于实验太长。这种理论水平产生的键角预测平均小了0.21度。在CCSD（T）/spdfg理论水平上预测的基本振动频率的平均精度优于8.0 cm-1，但其余的误差比几何参数的系统性差，除了X-Y拉伸通常被低估相对于实验。对于由单个行列式参考函数描述得相当好的分子，在CCSD（T）/spdfg理论水平上，单键和多键能分别在1.0和2.0 kcal/mol之内。本专著回顾了导致当前最先进技术水平的进展，并总结了已发表文献中的选定实例。
Due to formal and computational advances in coupled-cluster theory over the past few years, it is now possible to obtain very accurate molecular geometries, vibrational frequencies, heats of formation, binding energies, and vertical electronic excitation energies. For example, based on statistical analyses of a large number of calculations, it is shown that the CCSD(T)/spdfglevel of theory givesrXH,rXY (double bonds), andrXY (triple bonds) with an average error of 0.0010, 0.0020, and 0.0026 Å, respectively, with the theoretical bond distances usually too long relative to experiment. This level of theory yields bond angle predictions that are too small by 0.21 degrees on average. Fundamental vibrational frequencies predicted at the CCSD(T)/spdfglevel of theory are accurate to better than 8.0 cm-1on average, but the remaining errors are less systematic than those found for the geometrical parameters, except for X–Y stretches which are usually underestimated relative to experiment. For molecules described reasonably well by a single determinant reference function, single- and multiple-bond energies are given to within 1.0 and 2.0 kcal/mol, respectively, at the CCSD(T)/spdfglevel of theory. The present monograph reviews the advances that have lead to the current state-of-the art, and also summarizes selected examples from the published literature.