Density functional tight binding: values of semi-empirical methods in an ab initio era.
Density functional tight binding: values of semi-empirical methods in an ab initio era.
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DOI：
10.1039/c4cp00908h
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发表时间：
2014-07-28
期刊：
影响因子：
--
通讯作者：
Elstner M
中科院分区：
文献类型：
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作者：
Cui Q;Elstner M
半经验（SE）方法是从Hartree-Fock（HF）或密度泛函理论（DFT）通过忽略和近似电子积分而得到的。因此，引入了必须从参考计算和/或通过拟合到可用的实验数据来确定的参数。这导致计算方法比使用中等大小基组的标准HF/DFT方法快约2-3个数量级，而比经验力场方法（分子力学：MM）慢约3个数量级。因此，SE方法最适合特定范围的应用。这些包括研究含有大量原子的系统，因此对于从头算或DFT方法来说太大，以及动力学或熵效应特别重要的问题。在后一种情况下，考虑非常有限数量的分子结构或忽略熵贡献所产生的误差可能远远大于由于使用SE方法而损失的精度。SE方法有吸引力的另一个领域涉及可靠的MM模型不容易获得的系统的分析。因此，即使在从头算方法取得快速进展的时代，人们对进一步开发SE方法也有相当大的兴趣。我们通过讨论密度泛函紧束缚方法的最新发展和应用来说明这一点。
Semi-empirical (SE) methods are derived from Hartree-Fock (HF) or Density Functional Theory (DFT) by neglect and approximation of electronic integrals. Thereby, parameters are introduced which have to be determined from reference calculations and/or by fitting to available experimental data. This leads to computational methods that are about 2–3 orders of magnitude faster than the standard HF/DFT methods using medium sized basis sets while being about 3 orders of magnitude slower than empirical force field methods (Molecular Mechanics: MM). Therefore, SE methods are most appropriate for a specific range of applications. These include the study of systems that contain a large number of atoms and therefore being too large for ab initio or DFT methods and also problems where dynamic or entropic effects are particularly important. In the latter case, the errors made by considering a very limited number of molecular structures or neglecting entropic contributions can be much larger than the accuracy lost due to the use of SE methods. Another area where SE methods are attractive concerns the analysis of systems for which reliable MM models are not readily available. Therefore, even in an era when rapid progress is being made in ab initio methods, there is considerable interest in further developing SE methods. We illustrate this point by focusing on the discussion of recent development and application of the Density Functional Tight Binding method.