Synthesis, Crystal Growth, and Characterization of a New Nonlinear Optical Crystal: EBQ-T

A type of organic nonlinear optical (NLO) material EBQ-T (2-(4-ethoxystyryl)-1-methyl-quinolinium 4-methylbenzenesulfonate) is synthesized, and the EBQ-T crystal with a size of 11 x 5 x 2 mm(3) is grown by the evaporation method in methanol. Single crystal X-ray diffraction (XRD) analysis confirms that the EBQ-T crystal belongs to the non-centrosymmetric Cc space group, and the edge molecular orbital energy gap (HOMO-LUMO) is calculated. Proton nuclear magnetic resonance (H-1 NMR) and fourier transform infra-red (FT-IR) tests further verify the crystal functional group. The crystal has a high second-order nonlinear effect, and the second harmonic generation (SHG) efficiency is about 3 times that of the KDP crystal. The ultraviolet-visible-near infrared (UV-vis-NIR) absorption spectrum shows that the EBQ-T crystal has good transmission performance, which can be up to 76%. Additionally, thermal stability and electrical properties of the EBQ-T crystal are characterized.