Hexacyanoosmate(iii) chemistry: preparation and magnetic properties of a pentanuclear cluster and a Prussian blue analogue with Ni(ii)

Abstract

The hexacyanoosmate(III) anion was used to prepare a pentanuclear cyanide bridged molecular cluster with ligand-protected Ni(II) ions as well as the corresponding Prussian blue phase from a reaction with aqueous Ni(II) ions.

Facile Preparation of Paramagnetic RuIII and OsIII Hexacyanides

“…As we understood, this compound was used as a precursor for the synthesis of pentanuclear bimetallic clusters. However, in the synthetic details, this precursor appeared to be (18-crown-6-K) 4 Mo(CN) 7 , [11] and no crystallographic data of the corresponding complex is available. Miyasaka [12] also used (K@18-crown-6) 3 [M(CN) 6 ] (M = Fe 3+ ) as starting material, but no corresponding structural information was reported.…”

“…In our hands, for both compounds, and especially for the Ru derivative, these synthetic procedures were poorly reproducible; the yields were much lower than reported, and in both cases the purity of the compounds obtained were unpredictable. [7] as starting material was found in the literature. However, neither was its synthesis reported nor was any reference for results published earlier given by the authors.…”

“…Recent theoretical approaches have emphasized the use of highly anisotropic orbitally degenerated cyano complexes such as [Re (CN) 7 6 ] 3-for engineering SMMs with high blocking temperatures. [3] Communications confirming the potential of such synthons have appeared very recently.…”

Enhancing the Blocking Temperature in Single‐Molecule Magnets by Incorporating 3d–5d Exchange Interactions

“…In a paper devoted to hypothetical clusters that incorporate the [Os(CN) 6 ] 3À anion, Mironov [28] argued that the exchange coupling in linear Os-CN-M groups should be strongly anisotropic due to orbital contributions to the kinetic exchange. Parallel to the work reported in this paper, the first cyanide-bridged materials based on the hexacyanoosmateA C H T U N G T R E N N U N G (III) anion were reported by Dunbars group in the form of the pentanuclear complexes [{Ni-A C H T U N G T R E N N U N G (tmphen) 2 } 3 {Os(CN) 6 } 2 ]·6 MeCN [29] (tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline) and [30] Although the former cluster was shown to exhibit magnetic anisotropy, the sign of this anisotropy is incompatible with SMM behaviour. [31] As to the use of other 3d ions instead of Ni, theoretical considerations suggest that the magnetisation reversal barriers for the hypothetical trigonal bipyramidal Os clusters are unlikely to be pronounced.…”

An Unprecedented Charge Transfer Induced Spin Transition in an Fe–Os Cluster

“…These efforts led to the first documented case of CTIST 2 ] 2+ in acetonitrile leads to the formation of 1, which crystallizes in the centrosymmetric space group P2 1 /c as found for related TBP molecules (Figure 1). [16,17] The crystallographic data for 1 reveal that the average Fe À N(tmphen) bond length increases by 0.09-0.2 between 110 and 300 K, an indication that a change in the oxidation and/or spin states of these metal ions is occurring (Tables 1 and S1 in the Supporting Information). A large (ca.…”