  Atomically thin crystals have recently been the focus of attention in
particular after the synthesis of graphene, a monolayer hexagonal crystal
structure of carbon. In this novel material class the chemically derived
graphenes have attracted tremendous interest. It was shown that although bulk
graphite is a chemically inert material, the surface of single layer graphene
is rather reactive against individual atoms. So far, synthesis of several
graphene derivatives have been reported such as hydrogenated graphene
"graphane" (CH), fluorographene (CF) and chlorographene (CCl). Moreover, the
stability of bromine and iodine covered graphene were predicted using
computational tools. Among these derivatives, easy synthesis, insulating
electronic behavior and reversibly tunable crystal structure of graphane make
this material special for future ultra-thin device applications. This overview,
surveys structural, electronic, magnetic, vibrational and mechanical properties
of graphane. We also present a detailed overview of research efforts devoted to
the computational modeling of graphane and its derivatives. Furthermore recent
progress in synthesis techniques and possible applications of graphane are
reviewed as well.
