POLYMERIC CRYSTAL-STRUCTURE OF ISAQUO(MU-PYRAZINE-2,3-DICARBOXYLATO)STRONTIUM(II)

saquo(mu-pyrazine-2,3-dicarboxylato)strontium(II), SrC6H8N2O7 crystals have been studied by X-ray diffraction. The strontium ion is coordina ted by a heteroring nitrogen, Sr-N of 2.793 Angstrom, and one oxygen a tom belonging to a monodentate carboxylic group, Sr-O of 2.583 Angstro m, situated close to this nitrogen atom. Two oxygen atoms of carboxyli c groups belonging to adjacent complex molecules, Sr-O = 2.647 Angstro m and 2.914 Angstrom, bridge them into ribbons. Each oxygen atom of th e above group is also linked to the Sr ions belonging to adjacent ribb ons, Sr-O = 2.576 Angstrom and 2.620 Angstrom, forming molecular sheet s, which are parallel to the (010) plane. Each Sr ion coordinates also three oxygen atoms of water molecules (the average distance is 2.669 Angstrom. Hydrogen bonds of 2.66(1)-2.84 (1) Angstrom link the sheets into a 3-dimensional framework.