BONDED AND NONBONDED HYDROGEN IN DIAMOND-LIKE CARBON

The techniques of infrared absorption and vacuum ultraviolet Raman spe ctroscopy are applied to study the states of hydrogen in diamond-like a-C:H. It is shown that, along with the state covalently bonded with c arbon, there exists a quasi-free state of stretched H-2 molecules adso rbed by graphite-like structural fragments. A model of thermally-induc ed reversible transfer of hydrogen between the bonded and non-bonded s tates is suggested to describe the experimental results of thermal tre atment. The techniques of infrared absorption and vacuum ultraviolet R aman spectroscopy are applied to study the states of hydrogen in diamo nd-like a-C:H. It is shown that, along with the state covalently bonde d with carbon, there exists a quasi-free state of stretched H-2 molecu les adsorbed by graphite-like structural fragments. A model of thermal ly-induced reversible transfer of hydrogen between the bonded and non- bonded states is suggested to describe the experimental results of the rmal treatment. (C) 1998 Elsevier Science B.V. All rights reserved.