@article {5128, title = {Synthesis, structure and magnetic properties of 3D interpenetrating nets of M(pyrazine)[Au(CN)(2)](2) (M = Cu, Ni, Co) supported by aurophilic interactions}, journal = {Polyhedron}, volume = {20}, number = {11-14}, year = {2001}, note = {ISI Document Delivery No.: 451LWTimes Cited: 46Cited Reference Count: 517th International Conference on Molecule-Base Magnets (ICMM 2000)SEP 16-21, 2000SAN ANTONIO, TX}, month = {May}, pages = {1247-1254}, type = {Proceedings Paper}, abstract = {{New inorganic coordination polymers of the form M(pyrazine)[Au(CN)(2)](2) (M = Cu (1); Ni (2); Co (3)) have been prepared and the copper(II) analogue structurally characterised. The X-ray analysis revealed two 3D interpenetrating alpha -polonium networks consisting of 1D chains of Cu-pyrazine units connected by [Au(CN)(2)] bridges. The two networks are connected via weak aurophilic interactions (Au-Au: 3.4729(2) Angstrom). Thermogravimetric analysis of all three compounds indicated the robust nature of these 3D systems, with decomposition beginning at 260 (1), 406 (2) and 360 degreesC (3). The magnetic susceptibility of 1 shows a maximum in chi (M) at 5.0 K; these data could be fitted to the theoretical expressions for either a 1D or a 2D Heisenberg antiferromagnetic array (J = -2.74 cm(-1)}, keywords = {ANTIFERROMAGNET, aurophilic, COMPLEXES, COMPONENT, coordination polymers, CRYSTAL-STRUCTURE, Cu(II) complexes, cyanide ligands, DICYANOAURATE(I), FERROMAGNET, interactions, interpenetration, MAGNETIC PROPERTIES, NITRATE, NITROXIDE, Pyrazine}, isbn = {0277-5387}, url = {://000169804400021}, author = {Leznoff, D. B. and Xue, B. Y. and Stevens, C. L. and Storr, A. and Thompson, R. C. and Patrick, B. O.} } @article {5128, title = {Synthesis, structure and magnetic properties of 3D interpenetrating nets of M(pyrazine)[Au(CN)(2)](2) (M = Cu, Ni, Co) supported by aurophilic interactions}, journal = {Polyhedron}, volume = {20}, number = {11-14}, year = {2001}, note = {ISI Document Delivery No.: 451LWTimes Cited: 46Cited Reference Count: 517th International Conference on Molecule-Base Magnets (ICMM 2000)SEP 16-21, 2000SAN ANTONIO, TX}, month = {May}, pages = {1247-1254}, type = {Proceedings Paper}, abstract = {{New inorganic coordination polymers of the form M(pyrazine)[Au(CN)(2)](2) (M = Cu (1); Ni (2); Co (3)) have been prepared and the copper(II) analogue structurally characterised. The X-ray analysis revealed two 3D interpenetrating alpha -polonium networks consisting of 1D chains of Cu-pyrazine units connected by [Au(CN)(2)] bridges. The two networks are connected via weak aurophilic interactions (Au-Au: 3.4729(2) Angstrom). Thermogravimetric analysis of all three compounds indicated the robust nature of these 3D systems, with decomposition beginning at 260 (1), 406 (2) and 360 degreesC (3). The magnetic susceptibility of 1 shows a maximum in chi (M) at 5.0 K; these data could be fitted to the theoretical expressions for either a 1D or a 2D Heisenberg antiferromagnetic array (J = -2.74 cm(-1)}, keywords = {ANTIFERROMAGNET, aurophilic, COMPLEXES, COMPONENT, coordination polymers, CRYSTAL-STRUCTURE, Cu(II) complexes, cyanide ligands, DICYANOAURATE(I), FERROMAGNET, interactions, interpenetration, MAGNETIC PROPERTIES, NITRATE, NITROXIDE, Pyrazine}, isbn = {0277-5387}, url = {://000169804400021}, author = {Leznoff, D. B. and Xue, B. Y. and Stevens, C. L. and Storr, A. and Thompson, R. C. and Patrick, B. O.} } @article {3470, title = {ANTIFERROMAGNETISM AND METAMAGNETISM IN 1,4-DIAZINE AND PYRIDINE COMPLEXES OF NICKEL(II)}, journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie}, volume = {73}, number = {2}, year = {1995}, note = {ISI Document Delivery No.: QQ128Times Cited: 9Cited Reference Count: 54}, month = {Feb}, pages = {275-283}, type = {Article}, abstract = {Several nickel(II) complexes containing pyridine (py), pyrazine (pyz) or methylpyrazine (mepyz) have been synthesized and characterized by vibrational and electronic spectroscopy, differential scanning calorimetry, and magnetic susceptibility studies to cryogenic temperatures. A comparison of the magnetic properties of the polymeric diazine-bridged complexes, Ni(pyz)(2)X(2) (X = Cl or NO3), Ni(pyz)(p-CH3C6H4SO3)(2), Ni(mepyz)(NO3)(2), and Ni(pyz)(3)(CH3SO3)(2).CH3OH with those of the related monometallic systems, Ni(py)(4)X(2) (X = Cl, p-CH3C6H4SO3 or CH3SO3) and Ni(mepyz)(4)(NO3)(2).H2O provides evidence for weak antiferromagnetic coupling between metal centers mediated by bridging diazine ligands in the former group of compounds. The magnetic properties were analyzed employing a model for S = 1 which takes into account zero-field splitting and employs a molecular field term to account for weak magnetic exchange. The compounds Ni(pyz)Cl-2 and Ni(py)Cl-2, show metamagnetic behaviour with critical fields of 13 and 2 kOe, respectively, at 2 K. In these compounds nickel ions, linked in chains by bridging chlorides, exhibit intrachain ferromagnetic and interchain antiferromagnetic exchange. In Ni(pyz)Cl-2, bridging pyrazine ligands are considered to provide the pathway for the antiferromagnetic coupling resulting in a high critical field.}, keywords = {ANTIFERROMAGNETISM, BRIDGED COPPER(II) COMPLEXES, CHAIN, COMPLEXES, CRYSTAL-STRUCTURE, MAGNETIC EXCHANGE, METAMAGNETISM, MOLECULAR-STRUCTURES, NICKEL(II), polymer, Pyrazine, PYRIDINE, SUPEREXCHANGE MECHANISM, SUSCEPTIBILITY}, isbn = {0008-4042}, url = {://A1995QQ12800015}, author = {Otieno, T. and Thompson, R. C.} } @article {3469, title = {PYRIDAZINE COMPLEXES OF COPPER(II) NITRATE - SYNTHESIS AND STRUCTURAL AND MAGNETIC STUDIES}, journal = {Inorganic Chemistry}, volume = {34}, number = {7}, year = {1995}, note = {ISI Document Delivery No.: QP839Times Cited: 33Cited Reference Count: 44}, month = {Mar}, pages = {1718-1725}, type = {Article}, abstract = {{The pyridazine (pdz) complexes [Cu(pdz)(3)(NO3)(3)]Cu-2, 1, [Cu(pdz)(3)(NO3)(2)], 2, [Cu(pdz)(4)(NO3)(2)] 3, and [Cu(pdz)(4)(NO3)][NO3], 4, have been prepared and characterized by spectroscopic methods, magnetic susceptibility measurements and, for 1 and 4, by single crystal X-ray diffraction. 1 crystallizes in the monoclinic space group P2(1)/n, with a = 8.938(1) Angstrom}, keywords = {CRYSTAL-STRUCTURE, EXCHANGE, LIGANDS, Pyrazine, SERIES}, isbn = {0020-1669}, url = {://A1995QP83900018}, author = {Otieno, T. and Rettig, S. J. and Thompson, R. C. and Trotter, J.} } @article {3469, title = {PYRIDAZINE COMPLEXES OF COPPER(II) NITRATE - SYNTHESIS AND STRUCTURAL AND MAGNETIC STUDIES}, journal = {Inorganic Chemistry}, volume = {34}, number = {7}, year = {1995}, note = {ISI Document Delivery No.: QP839Times Cited: 33Cited Reference Count: 44}, month = {Mar}, pages = {1718-1725}, type = {Article}, abstract = {{The pyridazine (pdz) complexes [Cu(pdz)(3)(NO3)(3)]Cu-2, 1, [Cu(pdz)(3)(NO3)(2)], 2, [Cu(pdz)(4)(NO3)(2)] 3, and [Cu(pdz)(4)(NO3)][NO3], 4, have been prepared and characterized by spectroscopic methods, magnetic susceptibility measurements and, for 1 and 4, by single crystal X-ray diffraction. 1 crystallizes in the monoclinic space group P2(1)/n, with a = 8.938(1) Angstrom}, keywords = {CRYSTAL-STRUCTURE, EXCHANGE, LIGANDS, Pyrazine, SERIES}, isbn = {0020-1669}, url = {://A1995QP83900018}, author = {Otieno, T. and Rettig, S. J. and Thompson, R. C. and Trotter, J.} } @article {3185, title = {INTRAMOLECULAR SELECTIVITY OF MUONIUM TOWARDS CHLORINATED AROMATIC-COMPOUNDS}, journal = {Hyperfine Interactions}, volume = {87}, number = {1-4}, year = {1994}, note = {ISI Document Delivery No.: PA118Times Cited: 0Cited Reference Count: 166th International Conference on Muon Spin Rotation/Relaxation/ResonanceMAY 31-JUN 11, 1993MAUI, HI}, pages = {947-952}, type = {Proceedings Paper}, abstract = {Muon resonance studies show that muonium atoms (Mu) in ethanol add selectively to certain C-sites of aromatic compounds containing -Cl and -OH substituents. The sites chosen seem to be those carrying the lowest electron density. This helps to characterize Mu as a nucleophile in addition reactions and, in this respect, Mu differs from ordinary H-atoms. The study shows no apparent inter-molecular selectivity between a pair of aromatic solutes in an equimolar mixture, but strong intra-molecular selectivity in an ether composed of those two aromatic rings. This difference between intra- and inter-molecular selectivity is interpreted as kinetic in origin - arising from the {\textquoteright}caging effect{\textquoteright} of the solvent and peculiar to reactions close to the diffusion-controlled limit.}, keywords = {ADDITION-REACTIONS, AQUEOUS-SOLUTIONS, BENZOIC-ACID, HYDROGEN ISOTOPES, LEVEL-CROSSING RESONANCE, Pyrazine, WATER}, isbn = {0304-3843}, url = {://A1994PA11800018}, author = {Venkateswaran, K. and Stadlbauer, J. M. and Laing, M. E. and Klugkist, J. and Chong, D. P. and Porter, G. B. and Walker, D. C.} } @article {2888, title = {COMPLEX POLYMERIC CATIONS OF COPPER(I) WITH GRAPHITE-RELATED AND DIAMOND-RELATED LATTICES - CRYSTAL-STRUCTURES OF POLY-TRIS(MU-2,5-DIMETHYLPYRAZINE)DICOPPER(I) HEXAFLUOROPHOSPHATE AND POLY-BIS(MU-2,5-DIMETHYLPYRAZINE)COPPER(I) HEXAFLUOROPHOSPHATE}, journal = {Inorganic Chemistry}, volume = {32}, number = {9}, year = {1993}, note = {ISI Document Delivery No.: KZ801Times Cited: 94Cited Reference Count: 47}, month = {Apr}, pages = {1607-1611}, type = {Article}, abstract = {{Yellow crystals of composition [Cu2(2,5-me2pyz)3][PF6]2, 1, and orange-red ones of composition [Cu(2,5-me2-pyz)2] [PF6], 2, were obtained from the reaction Of Cu(ClO4)2-6H2O, KPF6, and 2,5-dimethylpyrazine in ethanol. Single-crystal X-ray diffraction studies on both are reported. Crystals of 1 are monoclinic}, keywords = {cobalt(II), EXCHANGE, LIGANDS, MAGNETIC-PROPERTIES, MOLECULAR-STRUCTURE, NITROGEN-HETEROCYCLES, PERCHLORATE, Pyrazine, SPECTRUM, TRIFLUOROMETHANESULFONATE}, isbn = {0020-1669}, url = {://A1993KZ80100015}, author = {Otieno, T. and Rettig, S. J. and Thompson, R. C. and Trotter, J.} } @article {2888, title = {COMPLEX POLYMERIC CATIONS OF COPPER(I) WITH GRAPHITE-RELATED AND DIAMOND-RELATED LATTICES - CRYSTAL-STRUCTURES OF POLY-TRIS(MU-2,5-DIMETHYLPYRAZINE)DICOPPER(I) HEXAFLUOROPHOSPHATE AND POLY-BIS(MU-2,5-DIMETHYLPYRAZINE)COPPER(I) HEXAFLUOROPHOSPHATE}, journal = {Inorganic Chemistry}, volume = {32}, number = {9}, year = {1993}, note = {ISI Document Delivery No.: KZ801Times Cited: 94Cited Reference Count: 47}, month = {Apr}, pages = {1607-1611}, type = {Article}, abstract = {{Yellow crystals of composition [Cu2(2,5-me2pyz)3][PF6]2, 1, and orange-red ones of composition [Cu(2,5-me2-pyz)2] [PF6], 2, were obtained from the reaction Of Cu(ClO4)2-6H2O, KPF6, and 2,5-dimethylpyrazine in ethanol. Single-crystal X-ray diffraction studies on both are reported. Crystals of 1 are monoclinic}, keywords = {cobalt(II), EXCHANGE, LIGANDS, MAGNETIC-PROPERTIES, MOLECULAR-STRUCTURE, NITROGEN-HETEROCYCLES, PERCHLORATE, Pyrazine, SPECTRUM, TRIFLUOROMETHANESULFONATE}, isbn = {0020-1669}, url = {://A1993KZ80100015}, author = {Otieno, T. and Rettig, S. J. and Thompson, R. C. and Trotter, J.} } @article {2887, title = {SYNTHESIS AND STRUCTURAL AND MAGNETIC STUDIES OF DIAZINE-BRIDGED COMPLEXES OF COPPER(II) CYANATE - CRYSTAL-STRUCTURE OF POLY[BIS(CYANATO-N)BIS(MU-METHYLPYRAZINE)COPPER(II)]}, journal = {Inorganic Chemistry}, volume = {32}, number = {20}, year = {1993}, note = {ISI Document Delivery No.: LZ815Times Cited: 48Cited Reference Count: 44}, month = {Sep}, pages = {4384-4390}, type = {Article}, abstract = {{Copper(II) cyanate complexes of composition CuLn(NCO)2, Where n is 1 for L = pyrazine (pyz), methylpyrazine (mepyz), and pyridazine (pdz) and n is 2 for L = mepyz and pyridine (py), have been prepared and characterized by vibrational, electronic, and electron spin resonance spectroscopy, differential scanning calorimetry, and magnetic susceptibility studies to cryogenic temperatures. A single-crystal X-ray diffraction study on Cu(mepyz)2(NCO)2 (C12H12CuN6O2), the first compound containing methylpyrazine to be characterized in this way, revealed a two-dimensional square lattice polymeric structure. Its crystals are monoclinic, P2(1)/c, with a = 10.480(2) angstrom}, keywords = {EXCHANGE, IONS, polymer, Pyrazine, PYRIDINE, SPECTRA, SUPEREXCHANGE}, isbn = {0020-1669}, url = {://A1993LZ81500037}, author = {Otieno, T. and Rettig, S. J. and Thompson, R. C. and Trotter, J.} } @article {2887, title = {SYNTHESIS AND STRUCTURAL AND MAGNETIC STUDIES OF DIAZINE-BRIDGED COMPLEXES OF COPPER(II) CYANATE - CRYSTAL-STRUCTURE OF POLY[BIS(CYANATO-N)BIS(MU-METHYLPYRAZINE)COPPER(II)]}, journal = {Inorganic Chemistry}, volume = {32}, number = {20}, year = {1993}, note = {ISI Document Delivery No.: LZ815Times Cited: 48Cited Reference Count: 44}, month = {Sep}, pages = {4384-4390}, type = {Article}, abstract = {{Copper(II) cyanate complexes of composition CuLn(NCO)2, Where n is 1 for L = pyrazine (pyz), methylpyrazine (mepyz), and pyridazine (pdz) and n is 2 for L = mepyz and pyridine (py), have been prepared and characterized by vibrational, electronic, and electron spin resonance spectroscopy, differential scanning calorimetry, and magnetic susceptibility studies to cryogenic temperatures. A single-crystal X-ray diffraction study on Cu(mepyz)2(NCO)2 (C12H12CuN6O2), the first compound containing methylpyrazine to be characterized in this way, revealed a two-dimensional square lattice polymeric structure. Its crystals are monoclinic, P2(1)/c, with a = 10.480(2) angstrom}, keywords = {EXCHANGE, IONS, polymer, Pyrazine, PYRIDINE, SPECTRA, SUPEREXCHANGE}, isbn = {0020-1669}, url = {://A1993LZ81500037}, author = {Otieno, T. and Rettig, S. J. and Thompson, R. C. and Trotter, J.} }