第一性原理问题汇总

XYG3泛函

xDH4Gau地址https://github.com/igor-1982/xDH4Gau

从费托合成反应过程中来看,PBE有时候比B3LYP好(CH3CH3+CH2->CH3CH2CH3,实验值-98.62,PBE误差-0.26,B3LYP误差-4.3),有时候更差(CO->C+O,实验值255.07,PBE误差-10.79,B3LYP误差2.72),所以需要更准确的泛函: doubly hybrid (参考:L, Y. Zhang; X, Xu ChemPhysChem 2012 13, 1486,来源:49期催化科学的第一性原理计算模拟第三讲:理论催化进阶——迈向精准化学)。

简介:xDH4Gau is a python script to obtain XYG3-type doubly hybrid (xDH) results using the standard Gaussian xx package (xx=03, 09 and/or 16),XYG3型泛函是一类重要的双杂化泛函,包括XYG3, XYGJ-OS, XYG7等。其中XYG3泛函由张颖、徐昕和W. A. Goddard III于2009年在PNAS杂志上发表。由于这类泛函使用了不同泛函来计算密度和能量(即能量泛函是非自洽的),使得用户往往不能简单地在常见程序中使用。目前,通过内置或非内置的形式可以做XYG3型泛函计算的程序包括但不限于:Q-Chem, Gaussian, PySCF, FHI-aims, ORCA, ...。The Python-based Simulations of Chemistry Framework (PySCF) is an open-source collection of electronic structure modules powered by Python. The package provides a simple, lightweight, and efficient platform for quantum chemistry calculations and methodology development. PySCF can be used to simulate the properties of molecules, crystals, and custom Hamiltonians using mean-field and post-mean-field methods. To ensure ease of extensibility, almost all of the features in PySCF are implemented in Python, while computationally critical parts are implemented and optimized in C. Using this combined Python/C implementation, the package is as efficient as the best existing C or Fortran based quantum chemistry programs. In addition to its core libraries, PySCF supports a rich ecosystem of Extension modules.

Even though PySCF There is no built-in double hybrid functional , But as long as you are familiar with the logic of double hybrid functions , Can make use of PySCF Write a few lines of code XYG3 Run script , This is in PySCF One of the issue There is a detailed discussion in :https://github.com/pyscf/pyscf/issues/911我们也可以利用现成的Py_xDH程序来完成这样的计算,Py_xDH是目前唯一的可做XYG3梯度、Hessian和极化率的公开程序。该程序的文档。提供了对XYG3定义的详细描述。由于该程序对于开发者以外的用户来说可能难以使用,从xDH4Gau到Py_xDH的接口程序正在开发中。

生物大分子计算

https://www.zhihu.com/question/367895554?utm_source=wechat_session&utm_id=0

泛函选择

最常用的泛函投票

什么时候用B3LYP泛函?

DFT-D简介

大体系弱相互作用计算的解决之道

用偶合簇运动方程计算分子的多光子吸收截面(2005),CCSD(T)

谈谈量子化学中基组的选择

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