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The title compound [Co(NH3)6] [Na(EDTA-4H)],3.5H2O has been synthesized, and its crystal structure has been determined from 2064 independent single-crystal reflections measured on a diffractometer. The crystals are tetragonal, space groupP4212, with unit-cell parametersa = 14.618(5) andc = 10.658(4) Å. There are four formula entities in the unit cell givingDc = 1.562(2) g cm-3 compared withDm = 1.56(1) g cm-3. The structure was solved by conventional Patterson and Fourier techniques, and refined by full-matrix least-squares methods to a final agreement factor of 3.6%. The compound contains two crystallographically independent octahedral [Co(NH3)6]3+ ions, with an average Co—N distance of 1.966(6) Å, and a seven-coordinate sodium ion which is coordinated to four carboxyl oxygens, two amine nitrogens, and a water molecule which bridges to another sodium ion. The EDTA is therefore acting in its normal hexadentate manner. The range of Na—O distances is 2.25 to 2.93 Å whereas the Na—N distance is 2.46 Å. The crystal structure is additionally stabilized by extensive hydrogen bonding among coordinated ammonias, carboxyl oxygens, and water molecules.

Palladium(II) complexes of an imine-thiophene ligand N,N' bis(1-methylenethiophene)-1,3-diaminopropane and an amine-phenol ligand N,N'-bis(2-hydroxybenzyl)1,3-diamino-2,2-dimethylpropane were synthesized by reacting K2PdCl4 with alcoholic solutions of the ligands. X-ray structures of the complexes were determined using data from a CAD-4 Nonius diffractometer (MoKa radiation). The structures were solved by conventional methods resulting inR factors of 0.044 and 0.061 using 1841 and 2241 independent reflections, respectively. Crystal data: Complex I, orthorhombic, space groupPbca,a=11.323(2),b=14.819(2),c=23.873(3)Å,V=4006(1)Å3,Z=8. Complex II: Space groupP21/c,a=9.169(2),b=31.920(4),c=8.902(6),ß=90.38(2)°,V=2605(1)Å3.Z=4. Both complexes showed coordination of the ligands through the nitrogens only while the sulphur and the oxygen atoms were uncoordinated. Square planar coordination is completed bycis chloro ligands.

a-Furilglyoxime (H2afdo) complexes of cobalt(III) were used to synthesize H2afdo-cobaloximes with thiourea, triphenylphosphine, and aniline astrans-axial ligands. Encapsulation of the H-bonded species with BF3:OEt2 resulted in stable BF2-capped macrocycles which mimic the central metal core of the biological molecules such as vitamin B12 etc. Solution chemistry and spectroscopic measurements of the BF2-macrocycles as well as H-bonded cobaloximes revealed six-coordinated cobalt(III) as the central atom and a short hydrogen bond in the case of latter. X-Ray structure of a representative complex [Co(Hafdo)2(thiourea)2]NO3 (Haldo=a-furilglyoxime anion) confirmed a pseudo-octahedral geometry around cobait(III) with thiourea bonded to axial positions. The oxygen atoms of furyl groups are not involved in any kind of bonding and the overall structure of the complex differs from that of the H2dmg-cobaloximes (H2dmg=dimethylglyoxime).

The structure of the title compound has been determined by three-dimensional X-ray diffaction techniques in two crystallographic modifications, containing a total of three symmetry-independent molecules. This has clearly established that the observed rather unusual six-coordinated geometry is not a result of crystal packing effects. The triclinic modification (P¯1) has cell dimensionsa = 10.600(3),b = 10.899(3),c = 10.585(4) Å, a = 95.8(1), ß = 85.4(1), and ? = 126.2(1) °. The observed density of 1.52 g cm-3 agrees well with the calculated density of 1.51 g cm-3, based on two molecules per unit cell. For the structure solution and refinement 3156 reflections measured with a scintillation detector and withF02 ? 3s(F02) were used and gave a final agreement factor (R) of 0.027. The monoclinic modification is described by the following:a = 27.630(1),b = 12.350(1),c = 17.777(1) Å,ß = 100.9(2) °, space group =C2/c,Z = 12,d0 = 1.48 g cm-3,dc = 1.489 g cm-3. The structure was solved and refined using 3289 reflections measured with a scintillation detector and withF02?3s(F02). The final agreement factor was 0.065.

The crystal structure of the title compound has been determined from 1623 independent reflections measured by scintillation methods. The compound cyrstallizes in the monoclinic space groupP21/c witha = 10.60(2),b = 18.40(5),c = 17.05(3) Å, ß = 116.7(2) °, andZ = 4. The structure was solved by Patterson and Fourier techniques and was refined by full-matrix least-squares methods toR = 0.066. As in tris(N, N-diethyldithiocarbamato)-methyltin(IV) the crystal structure consists of discrete, neutral, sevencoordinated tin complexes. The distorted pentagonal bipyramidal geometry of the tin atom is almost identical to that in the methyl complex, being formed by two sulfur atoms from each dithiocarbamate and a carbon atom of the butyl group which occupies one of the axial positions. Each dithiocarbamate ligand again has one Sn-S distance significantly shorter than the other. For the equatorial ligands the average difference is 0.18 Å with the minimum Sn-S distance 2.619(7) Å and the maximum 2.860(6) Å. For the ligand which bridges axial-equatorial, the Sn-S axial distance is 2.491(6) Å, while the Sn-S equatorial distance is 2.763(8) Å. The axial S-Sn-C angle is 166.3(5) °. The results are compared with those for other seven-coordinated tin(IV) structures and seven coordinated dithiocarbamate complexes of other metals.

The crystal structure of the title compound has been determined from 2919 independent reflections measured by scintillation methods. The crystals are monoclinic, space groupP21/n, with cell parametersa = 10.041(3),b = 10.712(4),c = 24.295(7) Å, ß = 93.17(5), andZ = 4. The structure was solved by Patterson and Fourier techniques, and refined by full-matrix least-squares methods toR = 0.058. The crystal structure consists of discrete, neutral, mononuclear, seven coordinated tin complexes. The geometry around the tin is a distorted pentagonal bipyramid with the methyl group axial, two dithiocarbamate ligands equatorial, and one dithiocarbamate bridging axial-equitorial. For the equatorial dithiocarbamates, each ligand has a short Sn-S distance [2.618(2) Å] and a longer Sn-S distance [2.761(12) Å]. For the other dithiocarbamate ligand there is a short axial Sn-S distance [2.481(2) Å] and a long equatorial Sn-S distance[2.817(2) Å]. The Sn-C distance has a rather normal value of 2.148(8) Å.

The crystal structure of [(C5H5N)2H]+[ZnBr3/2Cl3/2(C5H5N)]- has been determined and refined by full-matrix least-squares methods using X-ray (R, on ¦Fo¦, = 0.045 with 2291 reflections) and neutron (¯R, on ¦Fo¦, = 0.035 with 2030 reflections) diffraction data. The crystals of the compound are monoclinic, space groupP21/c witha = 12.728(1),b = 11.600(1),c = 13.354(1) Å, ß = 107.38(1) °,Z = 4,Dx = 1.68, andDm(flotation) = 1.69 g cm-3. The X-ray and neutron intensities were measured by the counter ?-2? scan technique with CuKa X-rays (? = 1.5418 Å) and neutrons with ? = 1.109 Å, respectively. An intramolecular N--H hydrogen bond holds pairs of pyridine molecules together in the lattice [N ? N, 2.737(3) Å]. The hydrogen atom is very asymmetrically disposed with N-H distances of 1.086(7) Å and 1.658(6) Å. The coordination about the zinc atom is tetrahedral with the nitrogen atom of the pyridine molecule in one tetrahedral position and different mixtures of the two halogen atoms in the other three positions. The important average bond distances from the neutron study are Zn-N [2.073(3) Å], Zn-Cl [2.251(2) Å], Zn-Br [2.394(3) Å], N-C [1.334(5) Å], C-C [1.378(5) Å], and C-H [1.075(7) Å].

A new rhodium(III) complex of an amine-phenol ligand N,NN'-bis-(2-hydroxybenzyl)1,3-diaminopropane was synthesized and characterized by X-ray diffraction studies. Diffraction data were collected by the?-2? scan method using MoKa. radiation. The structure was solved by conventional methods resulting in a final R factor of 0.037 for 1954 independent reflections (Fo>2s(Fo)). The structure consists of a dinuclear complex with two µ-hydroxy bridges between the two Rh atoms. The overall charge of the molecule is neutral due to deprotonation of all phenolic groups. Crystal data: triclinic, space groupP¯1,a=7.308(3)Å;b=9.586(3)Å,c=12.686(5)Å, a=87.51(2), ß=88.28(2), ?=71.70(3)°,V=866.6(6)Å3;Z=2.