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Utilization of binary information encoded in the charge configuration of quantum-dot cells (the quantum-dot cellular automata, QCA, paradigm) requires molecule-sized dots for room temperature operation. Molecular QCA cells are mixed-valence complexes, and the evaluation and functionalization of an unsymmetrical heterobinuclear, two-dot, Fe-Ru molecular QCA cell is described. The solid state structures of trans-RuCl(dppm)(2)(C[triple bond]CFc) (1) (dppm = methylbis(diphenylphosphane), Fc = (eta(5)-C(5)H(5))Fe(eta(5)-C(5)H(4))) and mixed-valence [trans-RuCl(dppm)(2)(C[triple bond]CFc)][BF(4)] (1a) as well as XPS and spectroscopic data suggest class II behavior suitable for the intended application. Utilization of the trans-Cl position of 1 permits functionalization for surface binding. Two "tailed" complexes of 1, trans-Ru(dppm)(2)(C[triple bond]CFc)(C[triple bond]CPhOCH(3)) (2) and trans-[Ru(dppm)(2)(C[triple bond]CFc)(N[triple bond]CCH(2)CH(2)NH(2))][PF(6)] (3), have been prepared and characterized. The solid state structure of 3 and multinuclear NMR experiments define the structures. In addition, the spectroscopic properties of all complexes and their mixed-valence species are used to define the effect of the substituent "tail" on mixed-valence properties. Further, the electrochemistry of these compounds permits assessment of the extent of perturbation of the substituents on the comproportionation constants and overall electrochemical stability. The complexes possess properties necessary for candidate QCA molecules. 相似文献
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Ghosh S Shang M Li Y Fehlner TP 《Angewandte Chemie (International ed. in English)》2001,40(6):1125-1128
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Hong Yan Alicia M. Beatty Thomas P. Fehlner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2001,113(23):4630-4633
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We present several sets of special directions for integration over solid angle of functions with full cubic symmetry which represent a major advance in precision and thus can be applied to problems which are beyond the scope of present techniques. For example, it is possible to determine the first eight moments of a Fermi surface accurately from measurements along only ten special directions. 相似文献
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Addition of the internal alkyne, 2-butyne, to nido-1,2-(Cp*RuH)2B3H7 (1) at ambient temperature produces nido-1,2-(Cp*Ru)2(μ-H)(μ-BH2)-4,5-Me2-4,5-C2B2H4 (2), nido-1,2-(Cp*RuH)2-4,5-Me2-4,5-C2B2H4 (3), and nido-1,2-(Cp*RuH)2-4-Et-4,5-C2B2H5 (4), in parallel paths. On heating, 2, which contains a novel exo-polyhedral borane ligand, is converted into closo-1,2-(Cp*RuH)2-4,5-Me2-4,5-C2B3H3 (5) and nido-1,6-(Cp*Ru)2-4,5-Me2-4,5-C2B2H6 (6) the latter being a framework isomer of 3. Heating 2 with 2-butyne generates nido-1,2-(Cp*RuH)2-3-{CMeCMeB(CMeCHMe)2}-4,5-Me2-4,5-C2B2H3 (7) in which the exo-polyhedral borane is triply hydroborated to generate a boron bound ---CMeCMeB(CMeCHMe)2 cluster substituent. Along with 3, 4, 5, 6, and 7, the reaction of 1 with 2-butyne at 85 °C gives closo-1,7-(Cp*Ru)2-2,3,4,5-Me4-6-(CHMeCH2Me)-2,3,4,5-C4B (8). Reaction of 1 with the terminal alkyne, phenylacetylene, at ambient temperature permits the isolation of nido-1,2-(Cp*Ru)2(μ-H)(μ-CHCH2Ph)B3H6 (9) and nido-1,2-(Cp*Ru)2(μ-H)(μ-BH2)-3-(CH2)2Ph-4-Ph-4,5-C2B2H4 (11). The former contains a Ru---B edge-bridging alkylidene fragment generated by hydrometallation on the cluster framework whereas the latter contains an exo-polyhedral borane like that of 2. Thermolysis of 11 results in loss of hydrogen and the formation of closo-1,2-(Cp*RuH)2-3-(CH2)2Ph-4-Ph-4,5-C2B3H3 (12). 相似文献
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The reaction of lead acetate with (CO)(9)Co(3)(&mgr;(3)-CCOOH) leads to the formation of [Pb{(CO)(9)Co(3)(&mgr;(3)-CCO(2))}(2)](n)(), I, in high yield. The structure of I exhibits unusual six-coordinate Pb(II) centers with two asymmetrical chelating cluster carboxylates (C(22)Co(6)PbO(22); triclinic P&onemacr;; a = 8.119(1), b = 14.346(2), c = 14.660(2) ?; alpha = 102.18(1), beta = 99.01(1), gamma = 97.30(1) degrees; Z = 2). One oxygen of each cluster carboxylate ligand bridges between adjacent lead atoms such that a chainlike extended structure is found in the solid state without the presence of solvent or water. I is converted stepwise on pyrolysis into two metastable forms of solid materials (designated LT and HT), each of which has been characterized spectroscopically. The hydrogenation of 2-butenal as a test reaction shows that the LT catalyst exhibits selectivities similar to previous LT materials derived from other cobalt cluster metal carboxylates and that the HT material is totally inactive. The observed release of the lead core metal under HT activation conditions totally inactivates the catalyst and demonstrates exposure of the core metal in the HT form of these novel catalysts. 相似文献