Chevrel Phases: Genesis and Developments

Abstract

This chapter summarizes the important role played by Marcel Sergent in the discovery in the Rennes Laboratory of the Chevrel-Phases, which stimulated considerable interest in the international solid state chemistry community, because of their remarkable superconducting properties. After a brief general introduction to this topic the seminal discoveries associated with these phases between 1970 and 1990 are described. After their initial synthesis and structural determination was discovered, it was necessary to establish their critical superconducting transition temperature, the critical magnetic field and the critical current density in wires, single crystals, and thin films. More recently their applications as battery materials, in catalysis and their thermo-electric properties have been studied and are briefly described. These phases opened up the way not only to a rich solid state chemistry, but also to a rich solution chemistry, which complemented the classical field of transition metal carbonyl clusters. The basic cluster units of the Chevrel-Phases continue to be studied in the Rennes laboratory by the heirs of Marcel Sergent and more widely in the international community.

Chevrel phases: synthesis, structure, and electrocatalytic applications

“…Eventually, the as-obtained product succeeded in detecting two new phases: FeMo( ii ) 3 S 4 and FeMo( iii ) 2 S 4 . 1 Later, CPs were assigned to these ternary molybdenum–sulfur compounds. In the subsequent 50 years, CPs were prepared using this method extensively.…”

“…Chevrel phases (CPs) are ternary molybdenum chalcogenides with a chemical formula M x Mo 6 T 8 (x Z 0), of which T is a chalcogen, and M is a transition metal. 1,2 As shown in Fig. 1, Chevrel et al reported the first preparation of CPs in 1971, 3 which caught widespread attention due to their superconductivity, arousing an upsurge of CP superconducting materials in 1970s-1980s.…”

The {Re4} Tetrahedral Cyanometalate Cluster Anion [{Re4(μ3-CCN)4}(CN)12]8– with Inner (μ3-CCN)3– Ligands and Its Features in Coordination of Cu2+ Cations

“…The properties of cluster compounds are determined by both the composition and geometry of the cluster core; thus, the search for methods of synthesis of new cluster complexes remains an urgent task in this chemistry. A classical method for the synthesis of cluster compounds of molybdenum, tungsten, and rhenium is high-temperature ampule synthesis from simple substances and binary compounds . In these syntheses, as a rule, chalcogenides and halides of the corresponding metals are used, as well as melts of alkali-metal and alkaline-earth-metal halides.…”