“…One strategy to enhance the hyperpolariability of the cations is by elongation of its π-conjugation system. Based on these studies, we have previously synthesized and reported the crystal structure of the pyridinium salts (Chanawanno et al, 2008;Chantrapromma et al, 2006Chantrapromma et al, , 2007Chantrapromma et al, , 2008Chantrapromma et al, , 2009Jindawong et al, 2005) in order to study for their NLO properties. We herein report the crystal structure of the title compound, (I), which is another pyridinium salt.…”