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Solid-state Compounds (solid-state + compound)
Selected AbstractsChemInform Abstract: Color and Conductivity in Cu2O and CuAlO2: A Theoretical Analysis of d10×××d10 Interactions in Solid-State CompoundsCHEMINFORM, Issue 24 2001Antonio Buljan Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Solid-state compounds of stereoisomers: cis and trans isomers of 1,2-cyclohexanediol and 2,3-tetralindiolACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2007Michael A. Lloyd The phases of 1,2,3,4-tetrahydro-2,3-naphthalenediol (or 2,3-tetralindiol) and of 1,2-cyclohexanediol have been investigated. The structure of a very stable 1:1 compound (or co-crystal) of the cis and trans isomers of 2,3-tetralindiol, the existence of which has been known for nearly a century, has finally been determined. No evidence of any analogous compound between the cis and trans isomers of 1,2-cyclohexanediol has been found. The formation of solid-state compounds of stereoisomers is rare; it probably occurs only if the crystal packing of at least one of the isomers is unfavorable, e.g. if at least one of the melting points is lower than expected. Compound formation is usually unlikely because of the difficulty of simultaneously optimizing the translational spacings for both isomers, but that packing problem is avoided in the cis/trans compound of 2,3-tetralindiol because the two isomers are in very similar environments. In the structures of the individual 2,3-tetralindiol isomers there are clear conflicts between the competing packing requirements of the 1,2-diol moiety and the aromatic ring system; these conflicts are resolved better in the co-crystal than in the structures of the individual isomers. [source] Cs6Nb4Se22 and K12Nb6Se35.3: two new compounds containing the M4Q22 building blockACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Jason W. Krizan The title compounds, namely hexacaesium tetraniobium docosaselenide and dodecapotassium hexaniobium pentatriacontaselenide, were formed from their respective alkali chalcogenide reactive flux and niobium metal. Both compounds fall into the larger family of solid-state compounds that contain the M2Q11 building block (M = Nb, Ta; Q = Se, S), where the metal chalcogenide forms dimers of face-shared pentagonal bipyramids. Cs6Nb4Se22 contains two Nb2Se11 building blocks linked by an Se,Se bond to form isolated Nb4Se22 tetrameric building blocks surrounded by caesium ions. K12Nb6Se35.3 contains similar Nb4Se22 tetramers that are linked by an Se,Se,Se unit to an Nb2Se11 dimer to form one-dimensional anionic chains surrounded by potassium ions. Further crystallographic studies of K12Nb6Se35.3 demonstrate a new M2Se12 building block because of disorder between an Se2, site (85%) and an (Se,Se)2, unit (15%). The subtle differences between the structures are discussed. [source] | ||||||||||