The First Heteropentanuclear Extended Metal‐Atom Chain: [Ni⁺Ru₂⁵⁺Ni²⁺Ni²⁺(tripyridyldiamido)₄(NCS)₂]

Abstract

This study develops the first heteropentametal extended metal atom chain (EMAC) in which a string of nickel cores is incorporated with a diruthenium unit to tune the molecular properties. Spectroscopic, crystallographic, and magnetic characterizations show the formation of a fully delocalized Ru2(5+) unit. This [Ru2]-containing EMAC exhibits single-molecule conductance four-fold superior to that of the pentanickel complex and results in features of negative differential resistance (NDR), which are unobserved in analogues of pentanickel and pentaruthenium EMACs. A plausible mechanism for the NDR behavior is proposed for this diruthenium-modulated EMAC.

Extraordinarily Large Ferromagnetic Coupling (J≥150 cm−1) by Electron Delocalization in a Heterometallic Mo≣Mo−Ni Chain Complex

“…Over the past decade, we and others have studied heterometallic extended metal atom chains (HEMACs), which contain a linear string of three or more metal centers supported by four triply bridging ligands. Of specific interest to this work are trimetallic HEMACs of the form M A ≣M A −M B in which a quadruply bonded pair of group VI metals is appended to a high‐spin divalent first row transition metal.…”

Manuel M. Baizer Award: J.‐i. Yoshida / Luigi Tartufari International Award in Chemistry: L. de Cola and S.‐M. Peng / Priestley Medal: J. K. Barton / Honorary Doctorate: P. J. Stang

“…Peng’s research interests are in crystallography and inorganic chemistry, including the synthesis of molecular metal wires. He has reported in Chemistry—A European Journal on heteropentanuclear extended metal‐atom chains,2a and in Angewandte Chemie on the reduction of hydroxyphenyl‐substituted boranes 2b. Peng is on the International Advisory Board of the European Journal of Inorganic Chemistry…”

Modulation of Band Gaps toward Varying Conductivities in Heterometallic One-Dimensional Chains by Ligand Alteration and Third Metal Insertion

“…28,31,32 Both EMACs and HEMACs are discrete chains of metal-bonded atoms, which is interesting not only from a theoretical point of view but also potential applications, particularly as nanoscale electronic devices, where single-molecule conductivities have been widely explored. 33−44 Compared with EMACs containing single metal species, HEMACs show negative differential resistance expecting a molecular rectifier 37,38 and an extraordinarily large ferromagnetic coupling through metal−metal bonds, 27 which is attributed to anomalous electronic structures induced by connecting multiple metals. Reproducible and welldefined synthesis of these compounds includes ligand-assisted reactions with conjugated polyenes and polydentate ligands; in these cases, the number of available coordination sites of a ligand determines the length of a metallic chain.…”