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Monoclinic C2/c Space Group (monoclinic + c_space_group)

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Chemistry100%

Selected Abstracts

Hybrid Organic/Inorganic Supramolecular Conductors D2[Au(CN)4] [D = Diiodo(ethylenedichalcogeno)tetrachalcogenofulvalene], Including a New Ambient Pressure Superconductor

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 30 2007
Tatsuro Imakubo
Abstract Five diiodo(ethylenedichalcogeno)tetrachalcogenofulvalenes, DIEDSS {2-(5,6-dihydro[1,3]diselenolo[4,5- b][1,4]diselenin-2-ylidene)-4,5-diiodo-1,3-dithiole}, DIET-STF {2-(4,5-diiodo-1,3-diselenol-2-ylidene)-5,6-dihydro[1,3]dithiolo[4,5- b][1,4]dithiine}, DIEDS-STF {2-(4,5-diiodo-1,3-diselenol-2-ylidene)-5,6-dihydro[1,4]diselenino[2,3- d][1,3]dithiole}, DIETSe {2-(4,5-diiodo-1,3-diselenol-2-ylidene)-5,6-dihydro[1,3]diselenolo[4,5- b][1,4]dithiine}, and DIEDSSe {2-(4,5-diiodo-1,3-diselenol-2-ylidene)-5,6-dihydro[1,3]diselenolo[4,5- b][1,4]diselenine},have been synthesized without the use of the highly toxic reagent CSe2, and their Au(CN)4 salts have been prepared by electrochemical oxidation. Characteristic I···N iodine bonds are constructed in all crystals, and their packing motifs are classified into two groups by the difference in the space group symmetry. The salt of DIEDSS crystallizes in the monoclinic C2/c space group and a novel helical supramolecular architecture is constructed by the strong and directional I···N iodine bond. On the other hand, the rest of the four salts crystallize in the triclinic P space group and their donor packing motifs belong to the so-called ,-type. Conducting properties of the ,-type salts strongly depend on the number and positions of the selenium atoms on the donor molecule. The salts based on the diselenadithiafulvalene (DSDTF) derivatives, DIET-STF and DIEDS-STF, show metal,semiconductor transition and the salt of fully selenated ,-donor DIEDSSe shows stable metallic behavior down to 1.6 K. On the other hand, (DIETSe)2[Au(CN)4] is semimetallic down to low temperature and the superconducting transition occurs at around 2 K (onset).(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]

Synthesis, Crystal Structure, and Second-Order Nonlinear Optical Properties of Ruthenium(II) Complexes with Substituted Bipyridine and Phenylpyridine Ligands

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2006
Laurence Labat
Abstract Two new ruthenium(II) complexes of formula [Ru(bpy)2(L1)][PF6] and [Ru(bpy)2(L2)][PF6]2 are reported. HL1 is a (nitrophenyl)ethenyl-substituted phenylpyridine ligand, and L2 is the bipyridine analogue of HL1. The X-ray crystal structure of [Ru(bpy)2(L1)][PF6] has been solved, and the compound is found to crystallize in the monoclinic C2/c space group. The electronic spectrum of the cyclometalated derivative [Ru(bpy)2(L1)][PF6] exhibits a low-lying transition that is red-shifted from 454 to 546 nm relative to that of the parent bipyridine-based complex, which reveals an important charge-transfer character. To support this assumption, the nonlinear optical properties were investigated by the hyper-Rayleigh scattering technique and indicate a molecular static hyperpolarizability (,0) equal to 230,×,10,30 cm5,esu,1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]

New Molecular Charge-Transfer Salts of TM-TTF and BMDT-TTF with Thiocyanate and Selenocyanate Complex Anions [TMTTF = Tetramethyltetrathiafulvalene; BMDT-TTF = Bis(methylenedithio)tetrathiafulvalene]

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2003
Marta Mas-Torrent
Abstract Three new charge-transfer salts of tetrathiafulvalene (TTF)-based donors with thiocyanato- or selenocyanato-metal complex anions have been synthesised. The salts isolated were [BMDT-TTF]4[Cr(NCS)6] (1), [TM-TTF]4[Cr(NCS)6]·2CH3CN (2) and [TM-TTF]4[Cr(NCSe)6]·2CH3CN (3) [BMDT-TTF = bis(methylenedithio)tetrathiafulvalene and TM-TTF = tetramethyltetrathiafulvalene]. Single crystals of compound 1 crystallise in the monoclinic C2/c space group with a = 37.286(3), b = 10.0539(6), c = 21.069(2) Å, , = 124.348(4)°, V = 6520.9(9) Å3 and Z = 4. Compound 3 was also suitable for an X-ray diffraction study, however the anionic part, [Cr(NCSe)6], was highly disordered and the best solution gave a final R factor of 16.4%. A solution was found for the monoclinic space group C2/m with a = 13.787(3), b = 19.507(3), c = 14.735(5) Å, , = 102.90(3)°, V = 3862.9(17) Å3 and Z = 2. For compound 1 there are several S···S close atomic contacts between the donors and acceptors, but there is no discernible magnetic exchange between ions. Such an interaction was previously observed in related salts such as [TTF][Cr(NCS)4(phenanthroline)2] and [donor][M(NCS)4(isoquinoline)2] [M = Cr, Fe and donor = TTF, BEDT-TTF or TM-TTF (tetramethyltetrathiafulvalene)]. Compounds 1 to 3 are all paramagnetic semiconductors in which the magnetic susceptibility is dominated by the Cr-containing anions. The structure-function relationship, along with a comparison with related compounds, indicates that there is no long-range magnetic order because there are no ,-stacking interactions between donor and acceptor; these types of interactions are seen in all of the bulk magnets of this type in which the donor spin is magnetically coupled to the anion. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]

Three-dimensional networks in bis(imidazolium) 2,2,-dithiodibenzoate and 4-methylimidazolium 2-[(2-carboxyphenyl)disulfanyl]benzoate

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2009
Linheng Wei
Cocrystallization of imidazole or 4-methylimidazole with 2,2,-dithiodibenzoic acid from methanol solution yields the title 2:1 and 1:1 organic salts, 2C3H5N2+·C14H10O4S22,, (I), and C4H7N2+·C14H10O4S2,, (II), respectively. Compound (I) crystallizes in the monoclinic C2/c space group with the mid-point of the S,S bond lying on a twofold axis. The component ions in (I) are linked by intermolecular N,H...O hydrogen bonds to form a two-dimensional network, which is further linked by C,H...O hydrogen bonds into a three-dimensional network. In contrast, by means of N,H...O, N,H...S and O,H...O hydrogen bonds, the component ions in (II) are linked into a tape and adjacent tapes are further linked by ,,,, C,H...O and C,H..., interactions, resulting in a three-dimensional network. [source]

Na1.50Mn2.48Al0.85(PO4)3, a new synthetic alluaudite-type compound

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2006
Frédéric Hatert
The first hydro­thermal synthesis of an Al-rich alluaudite-type compound, namely disodium dimanganese aluminium tris­(phosphate), which has been obtained at 1073,K and 0.1,GPa starting from the composition Na2Mn2Al(PO4)3, is reported. The crystal structure, which has been refined in the monoclinic C2/c space group, is identical to that of natural alluaudite. The structure consists of kinked chains of edge-sharing M1 and M2 octa­hedra, which contain Mn2+ and Al3+ ions. The chains are stacked parallel to {101} and are connected in the b direction by the P1 and P2 tetra­hedra. These inter­connected chains produce channels parallel to c, which contain the large A1 and A2, sites occupied by Na+ and Mn2+ ions. [source]