Related Experiment Video
Updated: Jan 26, 2026
05:51
Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
6.7K
Bond Fragility Spectra for the Double Proton-Transfer Reaction in the Formic Acid-Type Dimers.
Jarosław Zaklika1, Ludwik Komorowski1, Piotr Ordon2
1Department of Physical and Quantum Chemistry , Wrocław University of Science and Technology , Wyb. Wyspiańskiego 27 , 50-370 Wrocław , Poland.
The Journal of Physical Chemistry. A
|April 23, 2019
Summary
A new method using fragility spectra accurately tracks bond changes during reactions. This technique, applied to double proton transfer, correlates well with established chemical bond order theories.
Area of Science:
- * Quantum Chemistry
- * Theoretical Chemistry
- * Chemical Reaction Dynamics
Background:
- * Fragility spectra offer a novel approach to monitor bond dynamics during chemical reactions.
- * Double proton transfer (DPT) reactions, involving molecules like formic acid and its thio-analogues, serve as a key model system.
- * Understanding bond breaking and formation is crucial for predicting reaction pathways and kinetics.
Purpose of the Study:
- * To apply the newly developed fragility spectra method to analyze bond changes in DPT reactions.
- * To establish correlations between fragility spectra parameters and established chemical descriptors.
- * To validate the theoretical underpinnings of the fragility spectra method using established chemical principles.
Main Methods:
- * Application of the fragility spectra method to formic acid and its thio-analogues (HCXYH, X, Y = O, S).
- * Calculation of nondiagonal connectivity matrix elements and Wiberg bond orders.
- * Analysis of linear correlations between these calculated values.
- * Investigation of the relationship between the slope of these correlations and global softness/atomic numbers.
Main Results:
- * Highly accurate linear correlations were found between connectivity matrix elements and Wiberg bond orders.
- * The slope of these correlations was directly related to global softness and atomic numbers of bonded atoms.
- * These findings corroborate the conceptual Density Functional Theory (c-DFT) formula for fragility spectra.
- * Observed electron density changes align with previously reported curvature diagrams.
Conclusions:
- * The fragility spectra method provides a reliable tool for observing bond breaking and formation in chemical reactions.
- * The method's theoretical basis is supported by its correlation with established chemical concepts like global softness and bond orders.
- * Results demonstrate the utility of fragility spectra in understanding the electronic changes during double proton transfer reactions.
Related Concept Videos
02:37Types of Chemical Bonds
93.9K
Chemical bonding theories were pioneered by American chemist Gilbert N. Lewis. He developed a model called the Lewis model to explain the type and formation of different bonds. Chemical bonding is central to chemistry; it explains how atoms or ions bond together to form molecules. It explains why some bonds are strong and others are weak, or why one carbon bonds with two oxygens and not three; why water is H2O and not H4O.
93.9K
02:36Types of Chemical Bonds
23.3K
23.3K
03:26Acids, Bases and Neutralization Reactions
63.7K
An acid-base reaction is one in which a hydrogen ion, H+, is transferred from one chemical species to another. Such reactions are of central importance to numerous natural and technological processes, ranging from the chemical transformations within cells or lakes and oceans to the industrial-scale production of fertilizers, pharmaceuticals, and other substances essential to the society.
63.7K
02:48Ionic Bonding and Electron Transfer
48.9K
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
48.9K
02:43Peptide Bonds
82.6K
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
82.6K
02:49Bond Energies and Bond Lengths
31.3K
Stable molecules exist because covalent bonds hold the atoms together. The strength of a covalent bond is measured by the energy required to break it, that is, the energy necessary to separate the bonded atoms. Separating any pair of bonded atoms requires energy — the stronger a bond, the greater the energy required to break it.
31.3K