Ethyl-Substituted Stilbazolium Derivatives for Second-Order Nonlinear Optics

Preparation, properties and structures of 1-methyl-4-{2-[4-(dimethylamino)phenyl]ethenyl}pyridinium crystals with various counter anions

“…7. However, we have already found a similar crystal structure to 2j in a DAST derivative, i.e., 1-ethyl-4-{2-[4-(dimethylamino)phenyl]ethenyl}pyridinium p-nitrobenzenesulfonate 3h [16]. Since similar crystal structures have been found for SHGactive DAST derivatives, their crystal structures might be classified into several groups, e.g., Cc group for 2a, 2b, 2d, 2e, and 2m and P2 1 group for 2j and 3h.…”

“…These findings may be useful for solubility tuning, which is important to grow high-quality crystals, besides selection of alkyl groups attached to the cation portion [16] and utilization of mixed solvent [31]. Crystal growth by the slow cooling method were performed and crystal structures of three SHG-active compounds were clarified.…”

“…For crystal growth from solution, appropriate solubility of the crystal is required. Although solubility variation of the salts by changing alkyl groups attached to the cation part has been studied earlier [16], that by substituting anion has not been investigated in detail. In the previous experiment, we evaluated solubilities of DAST and DASC (2b in Fig.…”

Large‐Size Bulk and Thin‐Film Stilbazolium‐Salt Single Crystals for Nonlinear Optics and THz Generation

“…It has already been demonstrated that varying the counter-ion to optimize the crystal packing and orient the dipoles as parallel as possible is an effective molecular engineering strategy to develop ionic organic crystals with non-centrosymmetric structure. [17][18][19][20] Using this approach, we have reported the synthesis and crystal growth of DSNS (4-N,N-dimethylamino-4′-N′-methyl-stilbazolium 2-naphthalenesulfonate)-a promising DAST derivative with perfectly aligned chromophores, leading to a 50 % higher nonlinearity in the crystalline powder than DAST. [21] However, only very small crystalline needles of DSNS with a diameter of less than 100 lm could be grown.…”

Development of DAST-derivative crystals for terahertz waves generation

“…2 shows the solubility curves in the range of 35-60 1C. The solubility of DAST derivatives is generally affected by the terminal functional group of the ions [17,27]. Thus, MOPT and MONT with a methoxy group have high solubility to methanol.…”