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Updated: Aug 18, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
A new visualization scheme of chemical energy density and bonds in molecules
1Department of Engineering Physics and Mechanics, Kyoto University, Kyoto, 606-8501, Japan. akitomo@kues.kyoto-u.ac.jp
Abstract:
Covalent bond describes electron pairing in between a pair of atoms and molecules. The space is partitioned in mutually disjoint regions by using a new concept of the electronic drop region R(D), atmosphere region R(A), and the interface S (Tachibana in J Chem Phys 115:3497-3518, 2001). The covalent bond formation is then characterized by a new concept of the spindle structure. The spindle structure is a geometrical object of a region where principal electronic stress is positive along a line of principal axis of the electronic stress that connects a pair of the R(D)s of atoms and molecules. A new energy density partitioning scheme is obtained using the Rigged quantum electrodynamics (QED). The spindle structure of the stress tensor of chemical bond has been disclosed in the course of the covalent bond formation. The chemical energy density visualization scheme is applied to demonstrate the spindle structures of chemical bonds in H2, C2H6, C2H4 and C2H2 systems. [Figure: see text]. Field theory of the energy density.
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