Schematic diagram of six possible hydrogenated graphene configurations (a) and graphane crystal structures (b). (a) Configurations with equivalent hexagonal hydrocarbon rings. (b) side and top views of graphane crystal structure with chair, stirrup, twist-boat, boat-1, boat-2, and tricycle configurations, respectively. The red and blue balls correspond to carbon atoms with up and down hydrogenation, respectively, and the white balls are hydrogen atoms .
Zhou et al. Nanoscale Research Letters 2014 9:26 doi:10.1186/1556-276X-9-26