Hirshfeld partitioning method

Several forms of wf have already been used within the field of MQS. These methods include the Hirshfeld partitioning [30], Bader s partitioning based on the virial theorem within atomic domains in a molecule [64], and the Mulliken approach [65]. For more information on all the three methods, refer to Chapter 15. 

Figure 6.1 shows the stockholder decomposition of the theoretical deformation density of the cyanoacetylene molecule, H—Cs=C—C=N (Hirshfeld 1977b). The overlap density in the bonds is distributed between the bonded atoms. The assignment of part of the density near the hydrogen nucleus to the adjacent carbon atom manifests the difference between fuzzy and discrete boundary partitioning methods. 

Several other definitions of atomic charges have been published in the chemical literature. Among those, two methods have gained some popularity. Hirshfeld partitioning is based upon the stockholder principle . According to that principle, p(r) at each point is partitioned into atomic contributions, called densities of bonded. atoms , that are given by... 

Eskandaii K, Van Alsenoy C (2014) Hydrogen-hydrogen interaction in planar biphenyl a theoretical study based on the Interacting Quantum Atoms and Hirshfeld atomic energy partitioning methods. J Comput Chem 35 1883-1889... 

Different studies have appeared on fragment similarity using all the three partitioning schemes mentioned above, although in the case of the Hirshfeld method, the stockholder partitioning has also been applied directly to the similarity index [46,66,67]. 

The polarizability of methane sulfonic acid and its hydrated clusters with up to five water molecules has been calculated using the MP2 method and the 6-311 + + G(2df,p) basis set ° . The polarizabilities and the charges have then been partitioned onto the different entities using the iterative Hirshfeld... 

In this work, we use the fractional occupation Hirshfeld-I (FOHI) method, which is an extension of the Hirshfeld-I (HI) method to calculate atomic spin populations. In the original Hirshfeld method [17], a weight function is used to partition the molecular density p(r) into atomic densities Pair)-... 

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