Geldof D, Krishtal A, Blockhuys F, Van Alsenoy C
Department of Chemistry, University of Antwerp, Universiteitsplein 1, B2610 Antwerp, Belgium.
Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin Schrödinger Straße, D-67663 Kaiserslautern, Germany.
J Chem Phys. 2014 Apr 14;140(14):144104. doi: 10.1063/1.4870498.
In this work, a new partitioning method based on the FOHI method (fractional occupation Hirshfeld-I method) will be discussed. The new FOHI-D method uses an iterative scheme in which both the atomic charge and atomic dipole are calculated self-consistently. In order to induce the dipole moment on the atom, an electric field is applied during the atomic SCF calculations. Based on two sets of molecules, the atomic charge and intrinsic atomic dipole moment of hydrogen and chlorine atoms are compared using the iterative Hirshfeld (HI) method, the iterative Stockholder atoms (ISA) method, the FOHI method, and the FOHI-D method. The results obtained are further analyzed as a function of the group electronegativity of Boyd et al. [J. Am. Chem. Soc. 110, 4182 (1988); Boyd et al., J. Am. Chem. Soc. 114, 1652 (1992)] and De Proft et al. [J. Phys. Chem. 97, 1826 (1993)]. The molecular electrostatic potential (ESP) based on the HI, ISA, FOHI, and FOHI-D charges is compared with the ab initio ESP. Finally, the effect of adding HI, ISA, FOHI, and FOHI-D atomic dipoles to the multipole expansion as a function of the precision of the ESP is analyzed.
在本工作中，将讨论一种基于分数占据 Hirshfeld-I 方法（FOHI 方法）的新的划分方法。新的 FOHI-D 方法使用一种迭代方案，其中原子电荷和原子偶极都是自洽计算的。为了在原子上诱导出偶极矩，在原子自洽场计算过程中施加一个电场。基于两组分子，使用迭代 Hirshfeld（HI）方法、迭代 Stockholder 原子（ISA）方法、FOHI 方法和 FOHI-D 方法比较了氢原子和氯原子的原子电荷及固有原子偶极矩。将所得结果作为 Boyd 等人 [《美国化学会志》110, 4182 (1988); Boyd 等人，《美国化学会志》114, 1652 (1992)] 以及 De Proft 等人 [《物理化学杂志》97, 1826 (1993)] 的基团电负性的函数进行进一步分析。将基于 HI、ISA、FOHI 和 FOHI-D 电荷的分子静电势（ESP）与从头算 ESP 进行比较。最后，分析了将 HI、ISA、FOHI 和 FOHI-D 原子偶极添加到多极展开中对 ESP 精度的影响。
