Bildung und Schwingungsspektrum des Pentachloro-oxo-niobat(V)-Ions. Die Kristallstruktur von [As(C6H5)4]2NbOCl5 · 2 CH2Cl2

Formation and Vibrational Spectrum of the Pentachloro-oxo-niobate(V) Ion. Crystal Structure of As(C₆H₅)₄]₂NbOCl₅ · 2 CH₂Cl₂ As(C₆H₅)₄]₂NbOCl₅ is formed by reaction of NbOCl₃ with As(C₆H₅)₄]Cl in CH₂Cl₂; form the solution it crystallizes with two molecules of CH₂Cl₂. The i.r. and Raman spectrum is in accord with a NbOCl₅ ion of symmetry 4mm. The crystals are triclinic (space group P1 ) with the lattice constants a = 1043, b = 1187, c = 2269 pm, α = 97.4, β = 106.3 and γ = 101.4°. The crystal structure was determined with X-ray diffraction data and refined to a residual index of R = 0.042. In the structure there are two of each crystallographic independent As(C₆H₅)₄⁺ ions and CH₂Cl₂ molecules. The NbOCl₅ ion has an octahedral shape with a Nb? O distance of 197 pm.