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Valency
About: Valency is a research topic. Over the lifetime, 1632 publications have been published within this topic receiving 26141 citations.
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TL;DR: The SUZ-2 material as discussed by the authors is a crystalline material having, in the dehydrated form, the empirical formula: m(M.sub.xz/2 :.sub O.sub XO.
Abstract: A crystalline material having, in the dehydrated form, the empirical formula: m(M.sub.2/a O):X.sub.z O.sub.xz/2 :.sub.y YO.sub.2 (I) in which m is 0.5 to 1.5; M is a cation of valency a; X is a metal of valency x, selected from aluminium, boron, gallium, zinc, iron and titanium; z is 2 when x is an odd number, and z is 1 when x is an even number; y is at least 5; and Y is silicon or germanium; and having, in the calcined hydrogen form, an X-ray diffraction pattern including significant peaks substantially as shown in Table I herein. The material has been designated SUZ-2, and is used in the conversion of hydrocarbons or oxygenates.
TL;DR: The diamagnetic heterotrimetallic anion, [V(SNS)2{Ni(dppe)}2]−, was prepared by reducing (dppe)NiCl2 in the presence of the chelating metalloligand as mentioned in this paper .
Abstract: Mixed-valence complexes represent an enticing class of coordination compounds to interrogate electron transfer confined within a molecular framework. The diamagnetic heterotrimetallic anion, [V(SNS)2{Ni(dppe)}2]−, was prepared by reducing (dppe)NiCl2 in the presence of the chelating metalloligand [V(SNS)2]− [dppe = bis(diphenylphosphino)ethane; (SNS)3– = bis(2-thiolato-4-methylphenyl)amide]. Vanadium–nickel bonds span the heterotrimetallic core in the structure of [V(SNS)2{Ni(dppe)}2]−, with V–Ni bond lengths of 2.78 and 2.79 Å. One-electron oxidation of monoanionic [V(SNS)2{Ni(dppe)}2]− yielded neutral, paramagnetic V(SNS)2{Ni(dppe)}2. The solid-state structure of V(SNS)2{Ni(dppe)}2 revealed that the two nickel ions occupy unique coordination environments: one nickel is in a square-planar S2P2 coordination environment (τ4 = 0.19), with a long Ni···V distance of 3.45 Å; the other nickel is in a tetrahedral S2P2 coordination environment (τ4 = 0.84) with a short Ni–V distance of 2.60 Å, consistent with a formal metal–metal bond. Continuous-wave X-band electron paramagnetic resonance spectroscopy, electrochemical investigations, and density functional theory computations indicated that the unpaired electron in the neutral V(SNS)2{Ni(dppe)}2 cluster is localized on the bridging [V(SNS)2] metalloligand, and as a result, V(SNS)2{Ni(dppe)}2 is best described as a two-electron mixed-valence complex. These results demonstrate the important role that metal–metal interactions and flexible coordination geometries play in enabling multiple, reversible electron transfer processes in small cluster complexes.