STRUCTURE OF 4-CYANO-4'-IODOBIPHENYL AT 297-K AND 183-K

4'-Iodobiphenyl-4-carbonitrile, C13H8IN, M(r) = 305.12, monoclinic, P2(1)/c, Z = 8, Mo K-alpha, lambda = 0.71069 angstrom, F(000) = 1168. At 297 (2) K, a = 9.854 (2), b = 14.869 (3), c = 17.103 (5) angstrom, beta = 115.44 (2)-degrees, V = 2262.9 angstrom 3, D(x) = 1.791 (2) g cm-3, mu = 27.64 cm-1, R = 0.043 for 3950 reflections. At 183 (4) K, a = 9.766 (3), b = 14.850 (8), c = 16.806 (6) angstrom, beta = 115.24 (3)-degrees, V = 2204.6 angstrom 3, D(x) = 1.838 (4) g cm-3, mu = 28.37 cm-1, R = 0.054 for 6128 reflections. The two crystallographically independent molecules (A and B) are similar and both have the expected geometry and dimensions. Each molecule is part of a chain of crystallographically equivalent molecules with short intermolecular N...I distances [3.243 (8) and 3.180 (8) angstrom at 297 K] and approximately linear C-N...I-C in each chain. There is disorder such that between 1 and 2% of the molecules appear to have I and CN interchanged; presumably any particular chain is ordered but 1 to 2% of the chains are in the opposite direction to the majority.