Crystal structure of niobium tetrachloride

Niobium tetrahalide complexes with neutral diphosphine ligands

“…This probably reflects inadequate temperature control, since both reduction of the NbBr5 and disproportionation of NbBr4 occur over a small temperature range [28 However, NbCl4 was easily and cleanly converted into NbBr4 by refluxing with excess BBr3, a route described by Druce and Lappert 30 for many other bromides (although not previously used to obtain NbBr4). The PXD pattern of NbBr4 was noted to be very similar to the literature pattern for NbCl4, 24,31 except that the peaks were shifted to lower 2θ positions, consistent with the larger anions. Rietveld refinement produced a good fit to this structure ( showing the atom numbering scheme and with ellipsoids drawn at the 50% probability level.…”

“…24,28 We found that reduction of NbCl5 with Nb powder in a sealed tube at 350 °C gave, after removal of any residual NbCl5, a good yield of brown-black needle crystals of NbCl4. 24,29 These were identified as NbCl4 via PXRD (see Supplementary Information).…”

“…24,28 We found that reduction of NbCl5 with Nb powder in a sealed tube at 350 °C gave, after removal of any residual NbCl5, a good yield of brown-black needle crystals of NbCl4. 24,29 These were identified as NbCl4 via PXRD (see Supplementary Information). In contrast, repeated attempts to produce NbBr4 by a similar method from NbBr5 and Nb powder over a temperature range of 300-600°C, failed to give useful quantities of NbBr4, the products containing substantial amounts of Nb3Br8, NbOBr2 and NbBr5.…”

Halide-bridged polymers of divalent metals with donor ligands – structures and properties

“…The underlying geometry is encountered in the binary halide NbCl 4 [54]. In this inorganic solid shorter bonding intermetal distances and longer nonbonding separations alternate along the polymer strand whereas in the structures relevant for this review no direct metalmetal bonds and no formation of cation pairs are observed.…”

Reversible Lithium Insertion into LiNb6Cl19

“…The successive reaction of NbCl 5 with Nb metal leads to the niobium subchlorides NbCl 4 [1], Nb 3 Cl 8 [2,3] and Nb 6 Cl 14 [3] containing niobium dimers as well as trigonal and octahedral niobium clusters. Nb 3 X 8 (X = Cl, Br) has seven electrons per cluster.…”