Carbon: a suggested new hexagonal crystal form.
Evidence for a new polymorphic form of carbon, similar to but distinct from chaoite, has been discovered. It is trigonal, with a(0) = 5.33 angstroms and c(0) = 12.24 angstroms. It is produced along with chaoite on the surfaces of graphitic carbons under free-vaporization conditions at low pressures, with temperatures above approximately 2550 degrees K.
Whittaker
A G
AG
Wolten
G M
GM