highly oriented pyrolytic graphite

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 $3300 K$ .

Source:

PAC, 1995, 67, 473 (Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)) on page 495