Niobium disulfide

A number of nearly two-dimensional intercalates of formula [MY2(L)X] (Y = S, Se L = N donors x = 0.5 for L = py, Et2NH, Et3N, piperdine, etc.) with promising superconducting properties have been described.573 Niobium disulfide is an intercalation electrode in lithium batteries, whose effectiveness is close to that of titanium disulfide.574... 

Sriram MA, Kumta PN (1998) The thio-sol-gel synthesis of titanium disulfide and niobium disulfide. J Mater Chem 8 2453-2463... 

The properties of niobium (V) chloride are well known. Cesium hexachloroniobate(V) is a bright yellow, crystalline, moisture-sensitive compound. It is soluble in iodine (I) chloride, less so in iodine (I) chloride-thionyl chloride mixtures, and completely insoluble in thionyl chloride it is very slightly soluble in acetonitrile and nitromethane but insoluble in benzene, carbon disulfide, ethyl acetate, and diethyl... 

S). Similar compounds with bis(diphenylphoBphino)methane disulfide and the corresponding diselenide have also been prepared (Table X). These are the first examples of coordination of sulfur and selenium donors to actinide pentahalides and it will be interesting to see whether uranium pentahalides behave in a similar fashion since the analogous niobium(V) and tantalum(V) compounds are also known (43). 

Although many transition-metal derivatives react with cyclopropenes by ring opening (See Section 2.C. and ref 107 for examples), 1,2-dimclhylcyclopropene was regenerated from the complex 8 by reaction with triphenylphosphane or carbon disulfide, and a number of related nickel ° and niobium complexes of cyclopropenes which retain the three-membered ring have been reported. ... 

Because the sulfides of metals have a lower heat of formation than the oxides, some difficult-to-obtain metals can be made from their lulfides with aluminum. This process has been described by Gardner > for niobium (columbium) and tantalum from their disulfides (NbS and TaSj), whereby the relatively volatile by-product Al S, distills off above 1550°C. It is an interesting coincidence that the production of the same two metals by reduction of the pentoxides NbfOs and Ta s with silicon can be performed under formation of silicon (II) oxide (SiO), which volatilizes in vacuum. 

Nickel boride (Ni B) Nickel boride (Ni B) Nickel(II) bromide Nickel(II) chloride Nickel(II) fluoride Nickel(II) iodide Nickel(II) oxide Nickel(II) sulfide Nickel disulfide Nickel subsulfide Niobium... 

The development of niobium and tantalum dithiocarbamate chemistry is relatively recent, the first well authenticated examples coming from the insertion of carbon disulfide into metal amide complexes to give [M(S2CNR2)4] (193, 666). Dithiocarbamates are now known to stabilize niobium and tantalum in the +3 to +5 oxidation states. 

Addition of thiuram disulfides to the niobium(IV) dimethyl complex [Cp2NbMe2] results in cleavage of the sulfur-sulfur bond and addition to the metal center (734). The nature of the final product is dependent on the alkyl substituents. With tetraethylthiuram disulfide, the molecular niobium(V) dithiocarbamate complex [Cp2NbMe2(ri -S2CNEt2)2] results, which is believed to contain a monodentate dithiocarbamate ligand. In contrast, tetramethylthiuram disulfide affords a 1 1 electrolyte, believed to be [Cp2NbMe(S2CN-... 

---