The title compound, 9-iodo-1,2-diphenyl-1,2-dicarba-closododecaborane(9), C
14H19B10I, has the expected pseudo-icosahedral cluster geometry, with a cag
e C-C distance of 1.724 (4) Angstrom, comparable to that in the non-iodinat
ed parent. However, the twist angles, theta, of the phenyl rings are 2.1 (6
) and 27.6 (5)degrees, the latter being unusually large.