a1 Materials Research Centre and CSIR Centre of Excellence in Chemistry, Indian Institute of Science, Bangalore 560012, India, and Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
The HOMO-LUMO gaps have been estimated in a graphite-like sp2 carbon network with a progressive increase in the fraction of sp3 carbons, taking into account several possible structural alternatives for each composition. The gap is shown to increase exponentially with the fraction of sp3 carbons. Accordingly, the gap in a diamond-like sp3 network decreases with the increase in the fraction of sp2 carbons.
(Received August 23 1995)
(Accepted July 30 1996)
c1 a) Author to whom all correspondence should be addressed.