Fluoro-containing coordination compounds of chromium(III). V. Preparation and crystal structure of the Racemic Cis-[Cr(en)2F2]ClO4 · NaClO4 · H2O

Cis-[Cr(en)₂F₂]ClO₄ · NaClO₄ · H₂O (en = 1,2-diaminoethane) was obtained as the red crystalline product from the saturated solutions of both NaClO₄ and cis-[Cr(en)₂F₂]ClO₄ in water. The compound crystallizes in the monoclinic P2₁/n (No.14) space group with a = 9.540(2), b = 11.840(2); c = 14.659(3) Å, β = 95.02(1)°, Z = 4. The unit cell of the racemic crystal contains cis-[Cr(en)₂F₂]⁺ in the Λλλ and Δδδ enantiometric forms, Na⁺, ClO₄^?, and lattice H₂O. Cr has octahedral coordination. Cr? F and Cr? N bonds are 1.868(4), 1.887(5) and from 2.067(2) to 2.100(8) Å. Mean Cl? O bond is 1.38 Å. Na⁺ ions are in the distorted octahedral environment. Infrared spectrum confirms the presence of the lattice H₂O and proves the cis structure of [Cr(en)₂F₂]⁺.