Superlattice ordering in graphite-IC1 single crystals and fibers

By using X-ray diffraction, a 3-fold or 6-fold twinned monoclinic √(301) × 2 (-3.3°, 0°) superlattice (a = 4.92 A ̊, b = 42.68 A ̊, c = 7.0 A ̊, γ = 93.3°) was observed in stage-1 graphite-IC1 single crystals intercalated in IC1 vapor. This in-plane superlattice was also observed in stage-1 and stage-2 graphite-IC1, which were based on Thornel P-100 graphite fibers and prepared by the two-bulb method, in which liquid IC1 was at 95°C while graphite was at 100°C for stage 1 and 130°C for stage 2. This work provides the first observation of in-plane intercalate ordering in intercalated graphite fibers and the first X-ray diffraction evidence of IC1 intercalation in graphite fibers. A different in-plane superlattice was observed in stage-1 graphite-IC1 single crystals intercalated in IC1 liquid.