Bond Energy

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bond energy

[′bänd ‚en·ər·jē]
(physical chemistry)
The average value of specific bond dissociation energies that have been measured from different molecules of a given type.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Energy, Bond


the work required to break up a molecule into two parts (atoms, groups of atoms) and separate them an infinite distance from each other. For example, when considering the bond energy of H3C—H in a methane molecule, the two parts are the methyl group CH3 and the hydrogen atom H; when considering the bond energy of H—H in a hydrogen molecule, each hydrogen atom constitutes a part.

The bond energy is a specific case of binding energy and is generally expressed in kilojoules per mole (kJ/mole) or kilocalories per mole (kcal/mole). The value of the bond energy ranges from 8–10 to 1,000 kJ/mole, depending on the particles forming the chemical bond, the nature of the interaction between the particles (such as a covalent bond or hydrogen bond), and the multiplicity of the bond (for example, a double or triple bond). For molecules containing two or more identical bonds, the bond energy of each bond (bond dissociation energy) is distinguished from the mean bond energy, which is equal to the averaged value of the dissociation energy of the bonds. For example, the dissociation energy of the HO—H bond in a molecule of water, that is, the heat effect reaction H2O = HO + H, is equal to 495 kJ/mole; the dissociation energy of the H—O bond in a hydroxyl group is equal to 435 kJ/mole, and the mean bond energy is thus equal to 465 kJ/mole. The difference between the values of the bond dissociation energy and the mean bond energy is due to the fact that, during partial molecular dissociation (the breaking of one bond), a change occurs in the electron configuration and in the mutual arrangement of the remaining atoms in the molecule, thereby altering their interaction energy. The value of the bond energy depends on the initial molecular energy, which is sometimes referred to as the temperature dependence of bond energy. The bond energy is usually considered for cases where the molecules are in the standard state or at 0°K. These are the values of the bond energy commonly given in handbooks.

The bond energy is an important characteristic that determines the reactivity of a substance and is used in the thermodynamic and kinetic calculations of chemical reactions. It may be determined indirectly from given calorimetric measurements; it may also be determined by direct calculations and by means of mass spectroscopy and spectral analysis.


Energiia razryva khimicheskikh sviazei: Potentsialy ionizatsii i srodstvo k elektronu. Moscow, 1974.
Kireev, V. A. Kurs fizicheskoi khimii, 3rd ed. Moscow, 1975.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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Evaluation of the bond energy terms for the various types of boron-nitrogen bonds.
The value of bond energy in this literature is originated from either empirical electron theory, dangling bond analysis methods, atomic potential simulation, or density function theory which mostly are based on parameters such as covalent electron pairs, bond length, number of electron, contribution of couple effect between spin and orbit, bond capability, screen effect, electron density, and much other quantum chemistry information.
Stability and interaction strength non covalent on hemin-ligand complexes can be understood from the formation large bond energy. Bond energy derived from free energy released during the interaction of hemin-ligand complex.
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In bond-orbital model in binary compounds, if the imaginary (polar) component and real (covalent) compound are present, then the bond energy gap
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The inherent stability of silicone is due to the backbone structure, comprised of the silicone-oxygen polymeric bond, which has higher bond energy than a carbon-carbon bond that is the backbone of organic polymers.
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Ab initio calculations indicated a XeAu bond energy of about 100 kJ/mol, i.e., well into the regime for covalent bonds and much larger than expected for van der Waals bonding.
The "total bond energy" of a matrix, A, with M columns and N rows has been defined as:
Moreover, the curve that results for the 0@-90@ angles is smooth and can not be decomposed to calculate the hydrogen bond energy. In this case, the other solution for estimating the hydrogen bond strength is the simulation model described in the next section.