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Related Experiment Video

Updated: May 15, 2026

Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry

Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry

Published on: June 8, 2022

Shape entropy's response to molecular ionization.

K Pineda-Urbina¹, R D Guerrero, A Reyes

¹Facultad de Ciencias Químicas, Universidad de Colima, Carretera Colima-Coquimatlán Km. 9, Coquimatlán, Colima Col., CP 28400, Mexico.

Journal of Molecular Modeling

|January 8, 2013

Summary

We introduce shape entropy, a new measure of molecular electron distribution. This descriptor effectively quantizes electron delocalization and predicts changes in chemical bonding patterns upon ionization.

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Published on: June 8, 2022

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Published on: March 1, 2020

Area of Science:

Quantum Chemistry
Computational Chemistry
Theoretical Chemistry

Background:

Understanding molecular bonding properties is crucial in chemistry.
Existing descriptors may not fully capture electron delocalization dynamics.
Quantifying changes in bonding requires robust theoretical tools.

Purpose of the Study:

To define and explore a novel descriptor, shape entropy, for molecular bonding.
To investigate the relationship between shape entropy and electron delocalization.
To assess the utility of shape entropy's response to electron number changes for predicting bonding alterations.

Main Methods:

Definition of shape entropy via Shannon's entropy of the shape function.
Calculation of shape entropy and its linear response to electron number changes.
Application to selected molecular systems.
Analysis of the derivative of shape entropy in relation to the shape function and Fukui function.

Main Results:

Shape entropy accurately describes electron delocalization in molecules.
The linear response of shape entropy to ionization predicts modifications in bonding patterns.
The derivative of shape entropy is determined by the shape function and Fukui function.

Conclusions:

Shape entropy serves as a valuable descriptor for molecular bonding properties.
The proposed method offers insights into electron delocalization and bonding changes.
The derivative of shape entropy provides a direct link to fundamental electronic properties.