CRYSTAL-STRUCTURE OF THE 4-METHYLTHIO-4'-[3-SULFONATOPROPYL]-STILBAZOLIUM MONOHYDRATE ORTHORHOMBIC PHASE - A VERY EFFICIENT NONLINEAR-OPTICAL CRYSTALLINE MATERIAL

The orthorhombic phase of 4-methylthio-4'-[sulfonato-propyl]-stilbazolium monohydrate (C17H19 S2O3N, H2O) crystallizes in the space group Pc2(1)b (a = 6.989(4) angstrom, b = 12.430(6) angstrom, c = 20.59(1) angstrom; Z = 4). The crystal structure was solved by direct methods and refined by least-squares to a final unweighted R = 0.030 using 1351 non equivalent reflections. The role played by the water molecules in the molecular packing cohesion is emphasized and discussed. The angle between intramolecular charge transfer axis of stilbazolium entity and structural polar axis (73-degrees) shifted from the optimal orientation, in the mm2 point group, can lead to a high phase matchable nonlinear coefficient.