Hydrogen bis[tris(4-fluorophenyl)phosphane oxide] triiodide.
In the title compound, C(36)H(25)F(6)O(2)P(2)(+)·I(3)(-), hydrogen-bonded [{(p-FC(6)H(4))(3)PO}(2)H](+) dimers assemble along the crystallographic c axis to form channels that house extended chains of triiodide anions. Although the I-I bond lengths of 2.9452 (14) and 2.9023 (15) Å are typical, the inter-ion I...I distance of 3.5774 (10) Å is unusually short. A posteriori modelling of nonmerohedral twinning about (100) has been only partially successful, achieving a reduction in the maximum residual electron density from 5.28 to 3.24 e Å(-3). The inclusion of two low-occupancy I-atom sites (total 1.7%), which can be interpreted as translational disorder of the triiodide anions along the channels, reduced the maximum residual electron density to 2.03 e Å(-3). The minor fractional contribution volume of the nonmerohedral twin domains refined to 0.24 and simultaneous refinement of the inversion twin domains showed the crystal to be a 0.5:0.5 inversion twin.
School of Chemistry, University of Manchester, Brunswick Street, Manchester, England. farhad.haghjoo@postgrad.manchester.ac.uk
Farhad
F
Haghjoo
Nicholas A
NA
Barnes
Robin
R
Pritchard
Stephen M
SM
Godfrey
Shane
S
Ratcliffe