Design of single chain magnets through cyanide-bearing six-coordinate complexes

• Published in: Coordination chemistry reviews Vol. 249; no. 23; pp. 2691 - 2729
• Main Authors: Lescouëzec, Rodrigue, Toma, Luminita Marilena, Vaissermann, Jacqueline, Verdaguer, Michel, Delgado, Fernando S., Ruiz-Pérez, Catalina, Lloret, Francesc, Julve, Miguel
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2005
• Subjects: Bimetallic chains; Chains as magnets; Crystal structures; Cyanocomplexes; Magnetic properties; Polynuclear complexes; Preparation; saltmen 2; bpca; MeOsalen 2; bpym; Me 3tacn; ox 2; Hhfac; HB(pz) 3; 5-Brsalen 2; bt; dpa; phen; Cyanocomplexes; ampy; 5-MeOsalen 2; pyim; Bimetallic chains; AsPh 4; impy; H 2bqm; NEt 4; L 3; pao; L 2; Magnetic properties; Crystal structures; tach; NITPhOMe; Hacac; 2,4,6-tmpa 2; en; pbaOH 2; tacn; tetren; Chains as magnets; HPhSeO 2; Polynuclear complexes; PPh 4; B(pz) 4; dmphen; H 2L 1; dmbpy; Preparation; NBut; terpy; H 2apox; H 2pbqm; bipy
• ISSN: 0010-8545; 1873-3840
• DOI: 10.1016/j.ccr.2005.09.017

The design and preparation of stable cyanide-bearing six-coordinate complexes of formula [M III(L)(CN) x ] ( x + l − m)− (M = trivalent transition metal ion and L = polydentate blocking ligand) are summarized here. Their use as ligands towards either fully hydrated metal ions or coordinatively unsaturated preformed species, to afford a wide variety of low-dimensional metal assemblies whose nuclearity, dimensionality and magnetic properties can be tuned, is also reviewed. Special emphasis is put on the appropriate choice of the end-cap ligand L whose denticity determines the number of coordinated cyanide groups in the mononuclear precursors. Among the different new spin topologies obtained through this rational synthetic strategy, ferromagnetically coupled 4,2-ribbon like bimetallic chains which exhibit slow magnetic relaxation and hysteresis effects (chain as magnets) are one of the most appealing and constitute the heart of the present contribution.