Synthesis and X-ray studies of noncentrosymmetric merocyanine dyes—A series of organic nlo crystals

(E)-4-[4-(Dimethylamino)styryl]-1-methylpyridinium 4-bromobenzenesulfonate

“…(2009). E65, o217-o218 [doi:10.1107 Organic crystals with extensive conjugated π systems are attractive candidates for non-linear optic (NLO) studies because of their large NLO coefficients (Chia et al, 1995;Dittrich et al, 2003;Otero et al, 2002;Nogi et al, 2000;Sato et al, 1999). 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate (DAST) is one such promising NLO material (Adachi et al, 1999).…”

2-[(E)-2-(3-Hydroxy-4-methoxyphenyl)ethenyl]-1-methylquinolinium 4-methylbenzenesulfonate

“…The search for new organic materials that exhibit large molecular second-order optical nonlinearities is of considerable interest because of their wide range of potential applications, such as in the frequency doubling of lasers and optical data storage applications (Chemla & Zyss, 1987;Marder et al, 1991;Usman et al, 2000;Umezawa et al, 2002;Feng et al, 2005;Ye et al, 2005). Most organic crystals are colorless in the visible region, which are better for usage as non-linear optical (NLO) materials when compared with most inorganic crystals which are generally colored (Chemla & Zyss, 1987;Chia et al, 1995;Zhengdong et al, 1997). An organic crystal with delocalizedelectrons usually displays a large NLO response (Prasad & William, 1991).…”

“…Some organic materials are transparent in the visible region, which is good for nonlinear optical (NLO) materials compared with inorganic crystals [what exactly is being compared here?] (Chemla & Zyss, 1987;Chia et al, 1995;Zhengdong et al, 1997). An organic crystal with delocalized π-electrons usually displays a large NLO response (Prasad & William, 1991).…”

Bis[(E)-1-methyl-4-styrylpyridinium] 4-bromobenzenesulfonate iodide

“…For bond-length data, see: Allen et al (1987). For background to non-linear optical materials research, see: Chia et al (1995); Pan et al (1996); Prasad & Williams (1991). For related structures, see: Chantrapromma et al (2006); Fun, Chanawanno & Chantrapromma (2009a,b): Fun, Surasit et al (2009).…”

“…Organic molecules are promising candidates for the nonlinear optical (NLO) applications. Stilbene derivatives, especially the pyridinium stilbenes with Donor-π-Acceptor system, were recognized as a good organic NLO chromophore (Chia et al, 1995;Pan et al, 1996). We previously reported the systhesis and crystal structure of bis[(E)-1-methyl-4styrylpyridinium] 4-chlorobenzenesulfonate iodide (I), a pyridinium stilbene derivative, which crystallizes in noncentrosymmetric P2 1 space group and exhibits second-order NLO properties (Fun et al, 2009;Prasad & Williams, 1991).…”