Donor-acceptor complexes of halide ions with 1,4-diiodotetrafluorobenzene

(Ph4P)X as well as (Me4N)X (X = Cl, Br, I) react with 1,4-diiodotetrafluoro benzene in CH2Cl2 and CH3CN solutions, respectively, to give the donor-acce ptor complexes (Ph4P)(2)[(C6F4I2)Cl-2]. 4 CH2Cl2 (1), (Ph4P)(2)[(C6F4I2)Br- 2]. 2 CH2Cl2 (2), (Me4N)[(C6F4I2)Cl] (3), (Me4N)[(C6F4I2)Br]. CH3CN (4), (P h4P)(2)[(C6F4I2)(3)Br-2]. 4 CH2Cl2 (5), (Ph4P)(2)[(C6F4I2)(3)I-2] (6) and ( Me4N)(2)[(C6F4I2)(3)I-2] (7) All complexes have been characterized by singl e X-ray crystallographic structure determinations. 1: Space group <P(1)over bar>, Z = 1, lattice dimensions at 203 K: a = 1090 .2(1), b = 1206.2(1), c = 1242.8(1) pm, alpha = 91.84(1)degrees, beta = 106 .60(1)degrees, gamma = 99.84(1)degrees. 2: Space group <P(1)over bar>, Z = 1, lattice dimensions at 233 K: a = 1129 .7(2), b = 1183.9(1), c = 1293.4(1) pm, alpha = 65.52(1)degrees, beta = 65. 74(1)degrees, gamma = 89.02(1)degrees. 3: Space group P2(1)/n, Z = 4, lattice dimensions at 243 K: a = 714.8(1), b = 2405.7(3), c = 930.8(1) pm, beta = 96.38(1)degrees. 4: Space group P2(1)/c, Z = 4, lattice dimensions at 203 K: a = 1400.8(1), b = 1669.9(2), c = 795.9(1) pm, beta = 102.81(1)degrees. 5: Space group Pbca, Z = 4, lattice dimensions at 223 K: a = 2106.0(4), b = 1566.8(3), c = 2445.8(4) pm. 6: Space group <P(1)over bar>, Z = 1, lattice dimensions at 203 K: a = 1150 .9(1), b = 1278.9(1), c = 1292.9(2) pm, alpha = 65.47(1)degrees, beta = 82. 07(1)degrees, gamma = 83.62(1)degrees. 7: Space group Pbca, Z = 4, lattice dimensions at 223 K: a = 1210.5(5), b = 1429.0(6), c = 2470.3(12) pm. In all complexes the acceptor molecule C6F4I2 coordinates with the halide d onor ions in linear arrangements C-I ... X-. In 1 and 2 the halide ions act as terminal donors to form the dianionic species [X ... I-C6F4-I ... X](2- ) (X = Cl, Br). Complexes 3 and 4 form polymeric anionic zigzag chains with mu-X- bridges and bond angles I ... Cl ... I of 77.2 degrees and I ... Br ... I of 74.3 degrees. Complexes 5 - 7 are characterized by three-dimension al anionic networks via mu(3)-X- bridging halide ions and mu-bridging 1,4-d iiodotetrafluorobenzene molecules.