Term: bond-dissociation enthalpy
https://doi.org/10.1351/goldbook.08146

Definition:
Standard molar enthalpy required to break a given bond of some specific molecular entity by homolysis.

Note: Although \({\rm{D}}H^{\circ}\) is commonly used, \(\Delta_{\rm{diss}} H^{\circ}\) is more consistent with the notation for other thermodynamic quantities.

Example: For <span title="reaction">\(\ce{CH4 -> CH3. + H.}\)</span>, the bond-dissociation enthalpy is symbolized as <span title="symbol">\({\rm{D}}H^{\circ}(\ce{CH3-H})\)</span>.

Example: Array

Source: PAC, 2022, 94, 353. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)' on page 372 (https://doi.org/10.1515/pac-2018-1010)

Citation: 'bond-dissociation enthalpy' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.08146

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