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Density functional and X-ray diffraction studies of two polymorphs of N, N ’, N ”-triphenylguanidine

Authors: P.S.P. Silva, C. Cardoso, M.R. Silva, J.A. Paixão, A.M. Beja, F. Nogueira

Ref.: Journal of Molecular Structure 888, 92-98 (2008)

Abstract: The crystal structure of a new phase of triphenylguanidine has been solved by X-ray diffraction. The crystals are monoclinic, space group P2(1)/c, with a = 12.4060(4) angstrom, b = 15.1653(6) angstrom, c =8.7028(3) angstrom, beta =103.2482(15)degrees, Z = 4 and R = 0.0572. The crystal structure of the common orthorhombic phase of triphenylguanidine has been redetermined. The hydrogen bond patterns, in both polymorphs, delineate chains with C-1(1)(4) as the graph descriptor. Both crystal structures were optimized using Density Functional Theory within the Local-Density Approximation. The monoclinic phase is less stable, with an energy minimum 79.0 kcal/mol higher than the orthorhombic phase.

DOI: doi:10.1016/j.molstruc.2007.11.033

URL: dx.doi.org