Summary: Transformation of Diamond (sp 3 ) to
Graphite (sp 2 ) bonds by ion­impact.
David Saada \Lambda;y , Joan Adler \Lambda and R. Kalish \Lambda;y ,
\Lambda Department of Physics, Technion, Haifa, Israel
y Solid State Institute Technion, Haifa, Israel
December 4, 1997
The formation of point defects in diamond induced by an energetic dis­
placement of a carbon atom out of its lattice site and the relaxation of the
thereby disrupted crystal are studied by molecular dynamics simulations with
the Tersoff potential. The displacement energy for Frenkel pair creation is
calculated to be 52 eV, in agreement with experiments. It is found that
the !100? split­interstitial, with a bonding configuration which resembles
graphite, is the most stable defect, and the disrupted region around it is rich
in sp 2 ­like (graphitic) bonds. This region extends several nanometers and is
likely to be the elementary electrically conductive cell experimentally found
in radiation­damaged diamond.
Keywords: Molecular Dynamics, Structural Defects, Carbon
1

Diamond is very special owing to its exceptionally strong sp 3 bonds

Source: Adler, Joan - Physics Department, Technion, Israel Institute of Technology

Collections: Physics