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61.
Judith L. KissickAndrew R. Cowley Ann M. Chippindale 《Journal of solid state chemistry》2002,167(1):17-27
Two new gallium phosphates, [NH3(CH2)4NH3][Ga4(PO4)4 (HPO4)] (I) and [NH3(CH2)4NH3][Ga(PO4)(HPO4)] (II), have been synthesized under solvothermal conditions in the presence of 1,4-diaminobutane and their structures determined using room-temperature single-crystal X-ray diffraction data. Compound (I) (Mr=844.90, triclinic, space group P-1, a=9.3619(3), b=10.1158(3) and c=12.6456(5) Å, α=98.485(1), β=107.018(2) and γ=105.424(1)°; V=1070.39 Å3, Z=2, R=3.68% and Rw=4.40% for 2918 observed data [I>3(σ(I))]) consists of GaO4 and PO4 tetrahedra and GaO5 trigonal bipyramids linked to generate an open three-dimensional framework containing 4-, 6-, 8-, and 12-membered rings of alternating Ga- and P-based polyhedra. 1,4-Diaminobutane dications are located in channels bounded by the 12-membered rings in the two-dimensional pore network and are held to the framework by hydrogen bonding. Compound (II) (Mr=350.84, monoclinic, space group P21/c, a=4.8922(1), b=18.3638(6) and c=13.7468(5) Å, β=94.581(1)°; V=1227.76 Å3, Z=4, R=2.95% and Rw=3.37% for 2050 observed data [I>3(σ(I))]) contains chains of edge-sharing 4-membered rings of alternating GaO4 and PO4 tetrahedra constituting a backbone from which hang ‘pendant’ PO3(OH) groups. Hydrogen bonding between the GaPO framework and the diamine dications holds the structure together. A previously reported phase, [NH3(CH2)4NH3][Ga4(PO4)4(HPO4)] (V), structurally related but distinct from its stoichiometric equivalent, (I), has been prepared as a pure phase by this method. Two further materials, [NH3(CH2)5NH3][Ga4(PO4)4(HPO4)] (III) (tricli- nic, lattice parameters from PXD: a=9.3565(4), b=5.0156(2) and c=12.7065(4) Å, α=96.612(3), β=102.747(4) and γ=105.277(3)°) and [NH3(CH2)5NH3][Ga(PO4)(HPO4)] (IV) (Mr=364.86, monoclinic, space group P21/n, a=4.9239(2), b=13.2843(4) and c=19.5339(7) Å, β=96.858(1)°; V=1268.58 Å3, Z=4, R=3.74% and Rw=4.44% for 2224 observed room-temperature data [I>3(σ(I))]), were also prepared under similar conditions in the presence of 1,5-diaminopentane. (III) and (IV) are structurally related to, yet distinct from (I) and (II) respectively. 相似文献
62.
Fabrice O. M. Gaslain Ann M. Chippindale 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m537-m540
The title compound, {(C2H10N2)2[Mn(PO4)2]}n, contains anionic square‐twisted chains of formula [Mn(PO4)2]4− constructed from corner‐sharing four‐membered rings of alternating MnO4 and PO4 units. The Mn and P atoms have distorted tetrahedral coordination and the Mn atom lies on a twofold axis. The linear manganese–phosphate chains are held together by hydrogen‐bonding interactions involving the framework O atoms and the H atoms of the ethane‐1,2‐diammonium cations, which lie in the interchain spaces. 相似文献
63.
Handzy DO Bauer W Daffin FC Gaff SJ Gelbke CK Glasmacher T Gualtieri E Hannuschke S Huang MJ Kunde GJ Lacey R Li T Lisa MA Llope WJ Lynch WG Martin L Montoya CP Pak R Peaslee GF Pratt S Schwarz C Stone N Tsang MB Vander Molen AM Westfall GD Yee J Yennello SJ 《Physical review letters》1995,75(16):2916-2919
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Solvothermal synthesis affords access to the first truly three-dimensional antimony-sulfide framework which contains one-dimensional circular channels. 相似文献
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Zegers RG van Den Berg AM Brandenburg S Fleurot FR Fujiwara M Guillot J Hannen VM Harakeh MN Laurent H van Der Schaaf K van Der Werf SY Willis A Wilschut HW 《Physical review letters》2000,84(17):3779-3782
The (nat)Pb(3He,tp) reaction at E(3He) = 177 MeV was studied to identify 2Planck's over 2piomega isovector monopole strength in Bi isotopes. Monopole strength was found in the region -45
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70.
An analogy is stressed between the order-parameter symmetries of the two-dimensional d-pairing wave superconductors and of liquid-crystal mesophases formed from achiral bent-shaped molecules. It leads to a definition of a class of liquid-crystal states which are the analogs of the unconventional superconducting states, and are characterized by a loss of discrete symmetry operations of the parent state. 相似文献