量子化学Quantum chemistry

核心是在玻恩-奥本海默近似下求解电子薛定谔方程。主要方法包括：从头算方法（哈特里-福克、微扰理论 MP2、组态相互作用、耦合簇 CCSD(T)），精度可系统提高但计算量随体系增大急剧上升；密度泛函理论（DFT），以电子密度为基本变量，性价比高，是目前最常用的方法；半经验方法（休克尔、AM1、PM3），引入经验参数，适合大体系。

The core task is solving the electronic Schrödinger equation within the Born–Oppenheimer approximation. Ab initio methods (Hartree–Fock, MP2 perturbation theory, configuration interaction, coupled-cluster CCSD(T)) can be improved systematically but scale steeply with size; density functional theory (DFT), using electron density as the basic variable, offers the best cost–accuracy balance and is the most used today; semi-empirical methods (Hückel, AM1, PM3) add empirical parameters for large systems.

1927 年海特勒和伦敦用量子力学处理氢分子，标志着量子化学诞生。1930 年代鲍林发展价键理论，洪德和密立根发展分子轨道理论，休克尔提出 π 电子近似。1951 年罗特汉把哈特里-福克方程写成矩阵形式，便于计算机求解。1964–1965 年霍恩伯格、科恩和沈吕九奠定密度泛函理论。1998 年科恩和波普尔因发展密度泛函理论和量子化学计算方法获诺贝尔化学奖。

Heitler and London's 1927 quantum treatment of the hydrogen molecule marks the birth of quantum chemistry. In the 1930s Pauling developed valence bond theory, Hund and Mulliken molecular orbital theory, and Hückel his π-electron approximation. In 1951 Roothaan cast the Hartree–Fock equations in matrix form suitable for computers. Hohenberg, Kohn and Sham laid the foundations of density functional theory in 1964–65, and in 1998 Kohn and Pople shared the Nobel Prize in Chemistry for DFT and computational methods in quantum chemistry.

量子化学用于预测分子结构和振动光谱、计算反应活化能和过渡态、解释 NMR 化学位移和紫外光谱、设计催化剂和药物分子、筛选电池和光伏材料。Gaussian、ORCA、VASP 等软件已成为化学研究的常规工具。

Quantum chemistry predicts structures and vibrational spectra, computes activation energies and transition states, interprets NMR shifts and UV spectra, and helps design catalysts, drugs and battery and photovoltaic materials. Programs such as Gaussian, ORCA and VASP are now routine tools of chemical research.