Nanographene and graphene edge have electronic structures which crucially depend on the edges chirarity. Around zigzag edges, nonbonding edge state of π-electron origin is created, which is electronically, magnetically and chemically active, in spite of the absence of such state in armchair edge. The presence of edge state is a consequenceof broken symmetry of the pseudo-spin in massless Dirac fermion at the zigzag edge. This is interpreted also as the degradation of aromaticity in chemistry language. Meanwhile, the reaction of strongly chemically active species such as fluorine and hydrogen destroys the graphene π-conjugated hexagonal network, resulting in the creation of magnetic σ-dangling bond. Accordingly, the interplay of edge-state spins of π-electron origin and σ-dangling bond spins is an important issue in discussing the magnetism of nanographene and nanographite, the latter of which is a stack of nanographene sheets. We investigated the magnetic properties of nanographene/nanographite with the employment of magnetic susceptibility, ESR and X-ray absorption spectra (NEXAFS) for nanographene-network-based nanoporous carbon (activated carbon fiber (ACF)) and also fluorinated ACFs.
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