Term: char
https://doi.org/10.1351/goldbook.C00974

Definition:
A solid decompostion product of a natural or synthetic organic material.

Note: If the precursor has not passed through a fluid stage, char will retain the characteristic shape of the precursor (although becoming of smaller size). For such materials the term 'pseudomorphous' has been used. Some simple organic compounds, e.g. sugar, melt at an early stage of @D01547@ and then polymerize during @C00840@ to produce chars.

Related Terms:
1) decomposition (http://doi.org/10.1351/goldbook.D01547).
2) carbonization (http://doi.org/10.1351/goldbook.C00840).

Source: PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 484 (https://doi.org/10.1351/pac199567030473)

Citation: 'char' 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.C00974

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