A heteropentanuclear metal string complex [Mo₂NiMo₂(tpda)₄(NCS)₂] with two linearly aligned quadruply bonded Mo₂ units connected by a Ni ion and a meso configuration of the complex

Abstract

A dimeric molybdenum precursor and nickel ions are used to synthesize a symmetric heteropentanuclear complex, [MoNiMo(tpda)(NCS)]. This complex possesses unique structural features, as the four ligands are coordinated to the metal framework in a meso configuration. Furthermore, the central Ni ion is in a high spin state.

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.…”

Pentanuclear Heterometallic String Complexes with High‐Bond‐order Units [Ni23+−Mo24+−Ni2+(bna)4X2]3+ (X = Cl, NCS)

“…The corresponding molybdenum bond lengths in 1 and 2 are 2.13 and 2.11 Å, which correlate well with typical quadruple bond lengths of 2.06–2.17 Å reported in the literature . The distances between molybdenum and the adjacent nickel are 2.37 and 2.51 Å for 1 and 2.41 and 2.53 Å for 2 . Although the values of Ni─Mo spacing are smaller than the sums of the radii of molybdenum and nickel, we believe that the unusually short spacing is due to the helicity of bna − ligands rather than the formation of Mo─Ni bonds because, as the mentioned above, the dimolybdenum bond lengths are not longer than those of typical Mo 2 quadruple bonds.…”

Paramagnetic One-Dimensional Chain Complex Consisting of Three Kinds of Metallic Species Showing Magnetic Interaction through Metal–Metal Bonds

“…The study of heterometallic complexes continually leads researchers toward new compound creation by the combination of metallic species to afford diverse structural, electronic, magnetic properties, and catalytic activity. − Among these new compounds, heteronuclear metal string complexes (HMSCs), where two or three metals are regularly aligned as several strings with metal–metal bonds, have been the focus of attention due to their potential applications, which are not found in extended metal atom chains comprised of homometals. , For example, an asymmetric pentanuclear complex aligned as Ni–Ru–Ru–Ni–Ni shows a negative differential resistance expecting a molecular rectifier, and a heterotrimetallic complex aligned as Mo–Mo–Ni shows an extraordinarily large ferromagnetic coupling thorough metal–metal bonds, which are attributed to abnormal electronic structures induced by connecting multiple metals. Several HMSCs, − as well as pioneered heterometallic complexes, − have been reported. Rational and systematic synthesis methods are currently being explored and sequential synthesis methods for trinuclear complexes are suggested …”