Iterative Atomic Charge Partitioning of Valence Electron Density

We propose an atomic charge partitioning scheme, iterative adjusted charge partitioning (I-ACP), belonging to the stockholder family and based on partitioning of the valence molecular electron density. The method uses a Slater-type weighting factor c(A)r(2n-2)exp(-alpha(A)r), where alpha(A) is a fixed parameter and c(A) is determined iteratively. The parameters alpha(A) were fitted for 17 main-group elements. The I-ACP scheme is shown to produce consistent, chemically meaningful atomic charges. Several stockholder-type charge-partitioning are compared. Extensive numerical tests demonstrate that in most cases, I-ACP surpasses most other methods by reproducing more accurately molecular dipole moments. (c) 2018 Wiley Periodicals, Inc.