THE PHENOMENON OF CONGLOMERATE CRYSTALLIZATION. XXV. SPONTANEOUS RESOLUTION IN COORDINATION COMPOUNDS. THE CRYSTAL STRUCTURE OF [cis-Co(en)₂(NH₃)Br]Br₂

Br3CoN5C4H19, (I), crystallizes in the monoclinic system, space group C2/c, with cell constants a = 24.579(9),b = 8.665(3),c = 14.409(5) Å, and β = 92.69(3)˚; V = 2988.87 Å3 and d (MW = 435.875, Z = 8) = 2.097 gm cm−3. Data were collected in the range 4˚ ≤ 2θ ≤ 50˚, for a total of 2823 reflections, of which 1409 were independent and had I ≥ 3σ(I). The structure factors were corrected for absorption (μ = 90.882 cm−1) using psi scan curves obtained from reflections near X = 90˚. The transmission coefficients ranged from 0.68 to 0.99. The structure was solved by direct methods and refinement converged to final discrepancy indices of R(F) = 0.0601 and Rw(F) = 0.0663. The cobalt configuration and chelate ring conformations for (I) were found to be the preferred (lel)2-Δ(δδ) and Δ(λλ). The Co-N distances to the en rings are 1.961(6), 1.960(6), 1.977(6), 1951(6) Å, while that to the -NH3 ligand is 1.963(6) Å. The C-C distances are 1.52(1) and 1.50(1) Å; finally, the Co-Br distance is 2.403(1) Å.