2,9-Diiodo­hexa­cyclo­[9.3.1.1(2,6).1(4,8).1(9,13).0(1,8)]octa­deca­ne

The title compound, C(18)H(24)I(2), has an adamantanoid structure with tetra­hedral cages having four C atoms lying on the same plane [(I—)C—C—C—C(—I) torsion angle = 0°]. The plane is extended by the two I atoms, each having a deviation of 1.0 (6) Å [C—C—C—I torsion angle = 178.9 (4)°]. The central C—C bond connecting the two quaternary carbons seems enlarged [1.593 (9) Å] in comparison to the corresponding bond in [2]diadamantane [1.554 (3) Å]. This is attributed to the presence of the electronegative I atoms, which affect inductively the C atoms of the four-C-atom plane, making the central C—C bond weaker.