Abstract
The elasticity and hardness of a-C and a-C:H are related to their mean network coordinations. It is shown that sites contribute no rigidity if they form graphitic clusters, as suggested by experiment and electronic structure calculations, despite their having coordinations above the critical value 2.4. Hence both sites and polymeric = groups can severely lower the hardness of amorphous carbons.
- Received 11 February 1991
DOI:https://doi.org/10.1103/PhysRevLett.68.220
©1992 American Physical Society