Ghent Brussels Quantum Chemistry and Molecular Modeling alliance, Ghent, Belgium.
J Comput Chem. 2011 Dec;32(16):3485-96. doi: 10.1002/jcc.21933. Epub 2011 Sep 15.
For the Hirshfeld-I atom in the molecule (AIM) model, associated single-atom energies and interaction energies at the Hartree-Fock level are efficiently determined in one-electron Hilbert space. In contrast to most other approaches, the energy terms are fully consistent with the partitioning of the underlying one-electron density matrix (1DM). Starting from the Hirshfeld-I AIM model for the electron density, the molecular 1DM is partitioned with a previously introduced double-atom scheme (Vanfleteren et al., J Chem Phys 2010, 132, 164111). Single-atom density matrices are constructed from the atomic and bond contributions of the double-atom scheme. As the Hartree-Fock energy can be expressed solely in terms of the 1DM, the partitioning of the latter over the AIM naturally leads to a corresponding partitioning of the Hartree-Fock energy. When the size of the molecule or the molecular basis set does not grow too large, the method shows considerable computational advantages compared with other approaches that require cumbersome numerical integration of the molecular energy integrals weighted by atomic weight functions.
对于分子中的 Hirshfeld-I 原子（AIM）模型，在单电子 Hilbert 空间中，可以有效地确定 Hartree-Fock 水平上的单个原子能量和相互作用能量。与大多数其他方法不同，能量项与基础单电子密度矩阵（1DM）的划分完全一致。从 Hirshfeld-I 电子密度的 AIM 模型开始，分子 1DM 采用先前引入的双原子方案（Vanfleteren 等人，J. Chem. Phys. 2010, 132, 164111）进行划分。单原子密度矩阵是由双原子方案的原子和键贡献构建的。由于 Hartree-Fock 能量可以仅用 1DM 表示，因此后者在 AIM 上的划分自然会导致 Hartree-Fock 能量的相应划分。当分子的大小或分子基组没有太大增长时，与需要繁琐的原子权重函数加权的分子能量积分数值积分的其他方法相比，该方法具有相当大的计算优势。
