Growth of 4-N,N-Dimethylamino-4'-N'-methyl-stilbazolium Tosylate (DAST) Organic Single Crystals Controlled by Oleic Acid

Xin Wen,Huaxin Zhou,Mingang Zhang,Yu Gu,Xiaomeng Cheng,Xiangdong Xu,Xinfeng Liu,Jimmy Xu,Jia Shi,Lu Hu,Yangyang Jing,Ting Fan

doi:10.3390/cryst9100494

Abstract

4-N,N-Dimethylamino-4'-N'-methyl-stilbazolium Tosylate (DAST) organic single crystals controlled by (Z)-Octadec-9-enoic acid (oleic acid, OA) was grown by a slow-cooling method. The as-grown DAST single crystals were systematically characterized by FTIR, X-ray diffraction, second harmonic generation, and UV-vis spectroscopy. Results indicate that addition of OA into the DAST solutions leads to the controlled growth of DAST single crystals and consequently, the crystal quality and optical properties can be modified. Particularly, the DAST crystals grown under the control of OA exhibit larger sizes, higher crystallinities, and better optical qualities with higher optical band gaps and lower defect density, compared with those grown in the absence of OA. These results are helpful for better understanding the controlled growth of DAST organic single crystals and modifying their properties for practical applications.

Highlights

4-N,N-dimethylamino-40 -N0 -methyl-stilbazolium tosylate (DAST) organic single crystals controlled by (Z)-Octadec-9-enoic acid was grown by a slow-cooling method
Crystal grown without the OA control (Figure 2a), the morphology of the DAST crystal grown under the control of the OA is of an irregular hexagonal shape rather than a square platelet, but both crystals have the same crystal plane of (001) as the largest area
It is clear that the DAST crystal grown under the control of the OA exhibits similar IR features like that is clear that the DAST crystal grown under the control of the OA exhibits similar IR features like that of the DAST crystal grown without the OA control (Figure 3), both of which are in accordance with of the DAST crystal grown without the OA control (Figure 3), both of which are in accordance with those previously reported about DAST single crystals [18]

Summary

Introduction

4-N,N-dimethylamino-40 -N0 -methyl-stilbazolium tosylate (DAST) organic single crystals have attracted considerable attention, owing to their large nonlinear optical (NLO) susceptibility, high electro-optical (EO) coefficient, and low dielectric constant [1,2]. DAST single crystals with a large size, high crystallinity, and low defect density are generally required, by which higher. The growth of bulk DAST single crystals with a large size and high optical quality has remained a challenge [9,10]. We paid special attention to the effects of OA additives on the optical properties and quality of the as-grown DAST single crystals, which have been systematically investigated in this work by Fourier infrared spectroscopy (PE Spectrum 400, PerkinElmer Inco., Waltham, MA, USA), X-ray diffraction (XRD, X’Pert Pro MPD, Malvern Panalytical Ltd., Almelo, The Netherlands), UV-vis spectroscopy (UV-1700, SHIMADZU Co., Kyoto, Japan), and SHG measurements, respectively. The SHG measurements was carried out from a Ti:sapphire femtosecond pulse laser with 76 MHz pulse rate

Experimental Details

Results and Discussion

Photographs of theoflargest

The characteristic

Typical

Conclusions