Understanding and Reducing Errors in Density Functional Calculations
Understanding and Reducing Errors in Density Functional Calculations
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DOI：
10.1103/physrevlett.111.073003
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发表时间：
2013-08-15
影响因子：
8.6
通讯作者：
Burke, Kieron
中科院分区：
文献类型：
--
作者：
Kim, Min-Cheol;Sim, Eunji;Burke, Kieron
我们将变分密度泛函理论计算的能量误差分解为近似泛函和近似密度的贡献。通常，函数误差占主导地位，但在许多有趣的情况下，密度驱动的误差占主导地位。例子范围从计算电子亲合势到溶液中离子和自由基的优选几何形状。在这些异常情况下，密度泛函理论中的误差可以通过使用更精确的密度来大大减少。一个小的轨道间隙往往表明一个重大的密度驱动的错误。
We decompose the energy error of any variational density functional theory calculation into a contribution due to the approximate functional and that due to the approximate density. Typically, the functional error dominates, but in many interesting situations the density-driven error dominates. Examples range from calculations of electron affinities to preferred geometries of ions and radicals in solution. In these abnormal cases, the error in density functional theory can be greatly reduced by using a more accurate density. A small orbital gap often indicates a substantial density-driven error.