Poly[tris­(μ-2-amino­benzene-1,4-dicarboxyl­ato)tetra­kis­(N,N-dimethyl­formamide)­diyttrium(III)]

The asymmetric unit of the title coordination polymer, [Y2(C8H5NO4)3(C3H7NO)4]n, contains one Y3+ ion, three half-mol­ecules of the 2-amino­benzene-1,4-dicarboxyl­ate (abz) dianion and two O-bonded N,N-dimethyl­formamide (DMF) mol­ecules. Each abz half-mol­ecule is completed by crystallographic inversion symmetry and its –NH2 group is disordered in each case [relative occupancies within the asymmetric unit = 0.462 (18):0.538 (18), 0.93 (2):0.07 (2) and 0.828 (16):0.172 (16)]. The combination of disorder and crystal symmetry means that each of the four C—H atoms of the benzene ring of each of the dianions bears a statistical fraction of an –NH2 group. The coordination geometry of the yttrium ion is a fairly regular YO8 square anti­prism arising from its coordination by two DMF mol­ecules, four monodentate abz dianions and one O,O-bidentate abz dianion. The polymeric building unit is a dimeric paddle-wheel with two metal ions linked by four bridging abz dianions. Further bridging linkages connect the dimers into a three-dimensional framework containing voids in which highly disordered DMF mol­ecules are presumed to reside.