Abstract
The asymmetric unit of the title coordination polymer, [Y(2)(C(8)H(5)NO(4))(3)(C(3)H(7)NO)(4)](n), contains one Y(3+) ion, three half-mol-ecules of the 2-amino-benzene-1,4-dicarboxyl-ate (abz) dianion and two O-bonded N,N-dimethyl-formamide (DMF) mol-ecules. Each abz half-mol-ecule is completed by crystallographic inversion symmetry and its -NH(2) 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 -NH(2) group. The coordination geometry of the yttrium ion is a fairly regular YO(8) square anti-prism arising from its coordination by two DMF mol-ecules, 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 mol-ecules are presumed to reside.