Abstract. Mr= 902.83, triclinic, P1, a= 11.034 (2), b=11.166(2), c=9.431(3)A, ~t= 90.15 (2), b'= 115.10 (2), ~,= 81.30 (2) ° , V= 1037.7 (4)A 3, Z= 1, D x = 1.445 gcm -3, Mo Ko,, graphite monochromator, 2 = 0.71069 A, p = 1.002 cm -l, F(000) = 468, T= 295 K. The structure was refined using a rigid-group refinement procedure incorporating the TLS description of rigid-body motion to a final R of 0.062 for 281 variables and 1728 reflections. The structure is similar to that reported originally, except that the 4,4'-dinitrobiphenyl molecules, instead of conforming to mirror symmetry, are twisted by an average of 37.2 (1) ° about the central C-C bond. The 4-hydroxybiphenyl molecule is nearly planar. Its mean-square librational amplitude about the long molecular axis is 70 (5) deg 2, a value small enough that it is unlikely that it conceals a static disorder of two more twisted molecules.