Pyridine, complex cation, with chromium

When sodium chloride is fused with anhydrous chromium(II) chloride the product is NaCrCI5 regardless of the proportions of chlorides used.222 Other cations give tetra- or tri-chloro-chromates(II) as in Sections 35.3.7.3.ii and 35.3.7.3.vi above. The solvate [pyH]3[CrBr5]-2MeC02H has been isolated from the metal acetate and pyridine in a mixture of acetyl bromide and acetic acid, and there is considerable splitting of the spin-allowed d-d band in the reflectance spectrum of this complex,255 but no detailed investigations of pentahalochromates have been reported. 

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