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The crystal structure of Ag[Cu2(C~H404)~(OH)I.5H20, CI6H9AgCu209.5H20, has been determined from diffractometer data by Patterson and Fourier methods and refined to R = 0.079 for 2359 counter reflections: a = 11.388 (11), b = 11.772 (12), c = 7.875 (9) A, ,~ = 100.3 (1), fl = 80.2 (1), y = 102.2 (1) °, space group P i , Z = 2. The structure consists of centrosymmetric tetranuclear [ C u 2 ( C s H 4 0 4 ) 2 ( O H ) ] 2 2 anions (linked in polymeric chains by bridging ophthalate anions), Ag ~ cations and water molecules. The tetranuclear hydroxo-o-phthalatocuprate(II) anions contain two independent Cu atoms linked by triplybridging hydroxo O atoms and by carboxylate bridges from o-phthalate anions. The coordination polyhedron of Cu(1) is a trigonal bipyramid whose equatorial plane is tbrmed by three O atoms from three bridging carboxylates [ C u O = 2.049 (10), 2.101 (10), 2.233 (12) A], the axial positions being occupied by an O atom from an OHion [ C u O = 1.911 (11) A] and by an O atom from a monodentate carboxylate group [ C u O = 1.923 (11) AI. The coordination of Cu(2) is square pyramidal, the basal plane comprising two O atoms from OHions [ C u O = 1.955 (9), 1-949 (9) /k] and two O atoms from two bridging carboxylates [ C u O = 1-924(10), 1.928(10) AI. Another O atom from a bridging carboxylate is at the apex of the pyramid [ C u O = 2.352 (13) /k]. The Ag I ion is linked to this last O atom [ A g O = 2.264 (12) ,~,1 and to two water molecules [ A g O w = 2.328 (25), 2.536 (26) AI, and interacts with a benzene C C bond [ A g (midpoint of C C ) = 2.431 (16) ,~1, so that Ag-aromatic complexes, in a distorted tetrahedral configuration, are present.

[Cu(C5HsN)2(CaH404)] , M r = 385.9, is monoclinic, space group P21/c, with a = 18.199(6), b = 11.991 ( 1 4 ) , c = 1 7 . 9 2 3 ( 8 ) , ~ , f l = 119.98(2) ° , V = 3388 (4)/~ 3, Z = 8, D x = 1.51, D m = 1 . 5 1 M g m -3, F(000) = 1576, 2(Cu Ks) = 1.54178 ,A, #(Cu Ks) = 1.999 mm -~. R = 0.055 for 5425 observed reflections. 0567-7408/81/122159-05501.00 The structure consists of two crystallographically independent square-pyramidal [Cu(C 5HsN) 2 (C8H404)] complexes linked in polymeric chains by bridging phthalate anions which also act as chelating ligands through two O atoms from one carboxylate group. Pentacoordination of Cu involves two N atoms (one at the apex of the pyramid) from two pyridine molecules, one O atom from the monodentate carboxylate of an © 1981 International Union of Crystallography 2160 THE STRUCTURE OF (o-PHTHALATO)BIS(PYRIDENE)COPPER(I I ) o-phthalate anion and two 0 atoms from the bidentate chelating carboxylate of another o-phthalate anion. In the chains, held together by normal van der Waals contacts, C H . . . 0 interactions involving C atoms of pyridine and 0 atoms from chelating carboxylate

Calcium hydrazinecarboxylate, Ca(N'H2-NH-COO)2, forms monoclinic crystals, space group P21/c. The structure, determined by three-dimensional data, consists of metal-ligand complexes, where calcium exhibits coordination number 7, thus forming a pentagonal bipyramid. The complexes are joined in pairs, with Ca. • • Ca = 3.7/~, by bridging oxygen atoms which form bifurcated bonds with two calcium ions. The bridging oxygen atoms belong to ligands of other pairs, hence a three-dimensional network of complexes results. The two crystallographically independent ligand molecules are practically equal. The bonds and angles in them are compared with bonds and angles of the same ligand in octahedral complexes: the main differences concern the carbon-oxygen bonds of the carboxylic group. The structure

The crystal structure of carbohydrazide, OC(NH-NH2)2, has been determined from X-ray intensity data (Cu K~ radiation) measured with an automatic diffractometer. The space group is P2~/e with unit-cell dimensions a=3.728 (2), b=8.841 (3), c=12-659 (7) A; fl= 109-1 (1) °, V=394.3 /~3, Z=4. The structure was solved by the symbolic addition procedure and refined by the full-matrix least-squares method to R = 4 %. The molecule, depending upon rotations around the bonds C-N and N-N, has one -NH-NH2group in cis, gauche position (cis position with respect to C-O, with -NH2 in gauche position with respect to C-N) and the second group -NH-NHz in trans, antigauche position. The different conformational orientations do not alter appreciably bond distances and angles. The group of atoms N-CO-N is planar, with bond distances and angles practically equal to those in urea. One hydrogen bond N H . . . NH2-= 2.950/~, joins the molecules in chains parallel to [001] and weak hydrogen bonds, both N . . . O and N . . . N, connect the chains.