THE STAGE-2 HGCL2 GRAPHITE-INTERCALATION COMPOUND

The stage-2 graphite intercalation compound has been prepared for the first time by using a chlorine atmosphere with a pressure of 2.4 bar a nd heating the HgCl2, and highly oriented pyrolytic graphite at 250 de grees C for 2-4 months. The c-axis repeat distance is 12.79 +/- 0.08 A ngstrom. There is a strong de Haas-van Alphen effect with frequencies of 330 and 1013 T. They are explained by two bands of the Blinowski mo del. The Hall coefficient is independent of temperature between 4.2 an d 300 K, and has a value of 8.0 X 10(-9) m(3) C-1 corresponding to a c arrier concentration of (7.8 +/- 0.2) X 10(26) m(3) in the single-band model. (C) 1998 Elsevier Science S.A. All rights reserved.