Coexisting covalent and non-covalent planar networks in the crystal structures of {[M(bipy)2(NO3)2]•arene}n (M = Ni, 1; Co, 2; arene = chlorobenzene, o-dichlorobenzene, benzene, nitrobenzene, toluene or anisole)

The compounds {[M(4,4'-bipy)(2)(NO3)(2)].x arene}(n) (M=Ni, 1; Co, 2; x=2 for arene=chlorobenzene, o-dichlorobenzene, benzene, nitrobenzene or toluene; x=3 for arene=anisole) have been prepared and their crystal structures determined. All compounds represent rare examples of interpenetrating planar networks that are chemically different. It appears that the networks coexist because the (4,4) topology of the cobalt and nickel square grids is complementary to the (4,4) and (6,3) topology of the arene networks, resulting in inclined interpenetration and a 3-D architecture. This observation is discussed in the broader context of rational design strategies for hybrid solids.