论文标题
炼金术几何放松
Alchemical geometry relaxation
论文作者
论文摘要
我们建议使用炼金术扰动密度功能理论（APDFT）放松整个化学复合空间（CCS）的几何形状。 APDFT是指在Schrödinger方程的近似解决方案中涉及核电费变化的扰动理论。我们给出了一个分析公式，以在受限的Hartree-Fock案例中计算相对于核电和核位置（称为“炼金术力”）的混合二阶能量衍生物。我们已经实施并研究了该公式用于在各种参考和靶分子的几何学松弛中使用的公式。我们还分析了炼金术扰动系列的收敛性以及基集效应。与执行标准的Newton Raphson步骤时相比，将炼金术插值预测的能量，力和Hessian具有更准确的几何形状和平衡能量。我们对包括BF，CO，N2，CH $ _4 $，NH $ _3 $，H $ _2 $ O和HF收益率在内的小分子的数值预测，平衡能量的绝对错误和键长的绝对错误和小于10 MHA和0.01 BOHR的绝对错误，对于4 $^\ text {Text {Tht} $ order Apd forticaly for Appd apd forticality for 4 $^bohr。我们的炼金几何形状放松仍然保留了APDFT的组合效率：基于苯的单个耦合扰动的Hartree Hartree Fock衍生物，我们提供了平衡能量的数值预测和所有17个Iso-Electronic Bn含量突变体的平衡能量和放松的结构，并提供了A $ 27 MOR的$ 27 MOL $ \ sim $ 0.12 bohr。
We propose to relax geometries throughout chemical compound space (CCS) using alchemical perturbation density functional theory (APDFT). APDFT refers to perturbation theory involving changes in nuclear charges within approximate solutions to Schrödinger's equation. We give an analytical formula to calculate the mixed second order energy derivatives with respect to both, nuclear charges and nuclear positions (named "alchemical force"), within the restricted Hartree-Fock case. We have implemented and studied the formula for its use in geometry relaxation of various reference and target molecules. We have also analysed the convergence of the alchemical force perturbation series, as well as basis set effects. Interpolating alchemically predicted energies, forces, and Hessian to a Morse potential yields more accurate geometries and equilibrium energies than when performing a standard Newton Raphson step. Our numerical predictions for small molecules including BF, CO, N2, CH$_4$, NH$_3$, H$_2$O, and HF yield mean absolute errors of of equilibrium energies and bond lengths smaller than 10 mHa and 0.01 Bohr for 4$^\text{th}$ order APDFT predictions, respectively. Our alchemical geometry relaxation still preserves the combinatorial efficiency of APDFT: Based on a single coupled perturbed Hartree Fock derivative for benzene we provide numerical predictions of equilibrium energies and relaxed structures of all the 17 iso-electronic charge-netural BN-doped mutants with averaged absolute deviations of $\sim$27 mHa and $\sim$0.12 Bohr, respectively.
