Term: highly oriented pyrolytic graphite (HOPG)
https://doi.org/10.1351/goldbook.H02823

Definition:
Highly oriented pyrolytic graphite (HOPG) is a pyrolytic graphite with an angular spread of the c-axes of the crystallites of less than 1 degree.

Note: Commercial HOPG is usually produced by stress annealing at approximately 3300 K.

Related Terms:
1) pyrolytic graphite (http://doi.org/10.1351/goldbook.P04964).

Source: PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 495 (https://doi.org/10.1351/pac199567030473)

Citation: 'highly oriented pyrolytic graphite (HOPG)' 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.H02823

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