| Abstract
| - The structures of poly(1,4-phenylenesulfone), [1,4-ArSO2]n (Ar = 1,4-phenylene), and itstetrasulfone oligomer ArSO2ArSO2ArSO2ArSO2Ar (Ar = phenyl or 1,4-phenylene) have been determinedfrom X-ray powder diffraction data interfaced to molecular simulation and diffraction modeling. An initialmodel for the tetrasulfone oligomer was developed using conformational and packing information obtainedfrom a single-crystal X-ray determination of the structure of the trisulfone ArSO2ArSO2ArSO2Ar, in whichthe aromatic ring planes lie essentially orthogonal to a plane defined by the bridging C−S−C groups.Energy-minimization and crystallographic refinement of the tetrasulfone structure by Pawley and Rietveldmethods yielded an agreement factor (Rwp) of 15.3%., and an analogous approach led to solution of thecrystal structure of poly(1,4-phenylenesulfone) (Rwp = 5.5%). In all three structures, the diaryl sulfoneunits adopt near-perfect open-book conformations and the molecules crystallize with the aromatic ringsof laterally adjacent chains essentially parallel. The polymer unit cell is C-centered orthorhombic (twochains per cell), space group Cmcm, with a = 10.79, b = 5.05, and c = 9.97 Å. The polymer chain adopts21 helical geometry, and crystal packing is dominated by SO···H−C interactions (O···H = 2.68 Å).
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