The cations in (ferrocenylmethyl)triphenylphosphonium iodide, [{(C5H5)Fe(C5Ha)}CH2P(C6Hs)3]+.I -, (1), and in 1, l'-ferrocenediylbis(methyltriphenylphosphonium iodide) dichloromethane solvate, [Fe{(C5H4)CH2- P(C6H5)3}212+.2I-.CH2C12, (2), are involved in three dimensional networks of C--H. • .I- interactions between phenyl C--H groups and I- anions. In (1), the cation resides in a general position while one I- anion is on a twofold axis and a second I- anion is at an inversion centre. The shortest C...I- distances are 3.886 (2) and 3.989 (2)A to the I- ion which resides on an inversion centre. The cation in (2) has approximate mirror symmetry and lies in a general position in the unit cell along with its two I- anions. The shortest C--.I- interactions are 3.810 (4) and 3.886 (5) A,.