Date Published: May 01, 2009
Publisher: International Union of Crystallography
Author(s): Suchada Chantrapromma, Thawanrat Kobkeatthawin, Hoong-Kun Fun.
In the title compound, C16H15N2+·C6H4BrO3S−, the cation exists in the E configuration and is essentially planar with a dihedral angle of 3.10 (5)° between the pyridinium ring and the indole ring system. The π-conjugated planes of the cation and the anion are inclined to each other at a dihedral angle of 64.32 (4)°. In the crystal structure, the cations are stacked in an antiparallel manner along the a axis. The anions are linked into a chain along the a axis. The cations and the anions are linked into a three-dimensional network by N—H⋯O and weak C—H⋯O hydrogen bonds. The crystal structure is further stabilized by C—H⋯π interactions. A π–π interaction between the five-membered heterocyclic ring of the indole system and the pyridinium ring is also observed with a centroid–centroid distance of 3.5855 (7) Å.
For bond-length data, see: Allen et al. (1987 ▶). For background to non-linear optical materials research, see: Coe et al. (2003 ▶); Dittrich et al. (2003 ▶); Ogawa et al. (2008 ▶); Otero et al. (2002 ▶); Weir et al. (2003 ▶); Yang et al. (2007 ▶). For related structures, see, for example: Chanawanno et al. (2008 ▶); Chantrapromma et al. (2006 ▶, 2007 ▶, 2008 ▶, 2009 ▶); Jindawong et al. (2005 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).