An unusual field dependent slow magnetic relaxation and two distinct transitions were observed in a family of new rare earth-transition metal complexes, [Ln (bipy) (H2O)4 M(CN)6] ·1.5 (bipy) · 4H2O (bipy = 2,2’-bipyridine; Ln = Gd,Y; M = Fe, Co). The novel magnetic relaxation, which is quite different from those in normal spin glasses and superparamagnets but very resembles qualitatively those ...

Dinuclear and trinuclear ferrocene complexes {[Fc2BMe2]Li, [Fc-BMe2-fc-BMe2-Fc]Li2, Fc2B(pyind), [Fc2B(bipy)]PF6, [Fc-B(bipy)-fc-B(bipy)-Fc](PF6)2} bearing anionic, uncharged, and cationic four-coordinate boron bridges have been synthesized (Fc: ferrocenyl; fc: 1,1'-ferrocenylene; pyind: 5-fluoro-2-(2'-pyridyl)indolyl; bipy: 2,2'-bipyridyl). The molecular structures of [Fc2BMe2]Li(12-crown-4)2,...

Ag(I)-Ag(I) interactions in supramolecular structures have been achieved through the use of structural support from the ligand frames. In structures involving simple ligands like pyridine, strong π-π interaction leads to spatial ordering of the individual [Ag(L)2]+ units. In such structures anions also play a crucial role in dictating the final arrangement of the [Ag(L)2]+ synthons. In order to...

Stirring Lewis-basic transition metal complexes with the salts M[BAr(Cl)4] (M = Ag, Tl; Ar(Cl) = 3,5-C6H3Cl2) resulted in the formation of diplatinum complexes [{(Cy3P)2Pt}2(μ-Ag)][BAr(Cl)4] (3) and [{(Cy3P)2Pt}2(μ-Tl)][BAr(Cl)4] (4) and the diiron compound [{(OC)3(Me3P)2Fe}2(μ-Ag)] (5) featuring bridging, unsupported metal cations. Their properties were investigated by multinuclear NMR spectro...

the synthesis and single-crystal x-ray structure determination of the title compound [(bipy) , pb(0 ,cme) (o clo )] (1) and [(bipy) pb(clo ) ] (2) is described. compound (i) crystallizes in the triclinic space group p1(2), a= 7.384(2), b= 12.824(3), c= 10.622(6) a, ?= 73.41(2), ?= 80.98(2), ?= 73.68(2)', z= 2, and r =0.033 for 3408 independent reflections .compound (2) crystallizes in the ...

A series of cationic, ditopic N-donor ligands based on 4,4'-bipyridine (4,4'-bipy), 3-aminopyrazine (apyz) and 2-aminopyrimidine (apym), each incorporating two positively-charged N-heterocycles linked by a conformationally-flexible spacer unit, have been synthesised and treated with palladium(II) or platinum(II) precursors [M(2,2'-bipy)(NO(3))(2)] (M = Pd(II) or Pt(II)) to form highly cationic ...

Six substituted ligands based upon 2-(naphthalen-1-yl)quinoline-4-carboxylate and 2-(naphthalen-2-yl)quinoline-4-carboxylate have been synthesised in two steps from a range of commercially available isatin derivatives. These species are shown to be effective cyclometallating for IrIII, yielding complexes the form [Ir(C^N)2(bipy)]PF6 (where C^N=cyclometallating ligand; bipy=2,2′-bipyridine). X-r...

The electron capture dissociation (ECD) of metallo-supramolecular dinuclear triple-stranded helicate Fe(2)L(3)(4+) ions was determined by Fourier transform ion cyclotron resonance mass spectrometry. Initial electron capture by the di-iron(II) triple helicate ions produces dinuclear double-stranded complexes analogous to those seen in solution with the monocationic metal centers Cu(I) or Ag(I). ...