Structural, Optical, and Dielectric Properties of LCN Single Crystals

Abstract

A new organic nonlinear optical material, L-cysteinium nitrate (LCN), has been synthesized and grown as a single crystal. It was found that the system of the crystal structure by X-ray diffraction is orthorhombic with a noncentrosymmetric space group in favour of second harmonic gener- ation. The material has good optical transmission properties with 220 nm considered to be its cut-off in the UV area and 5.63 eV being its optical band gap. It is worth mentioning that the second harmonic generation ef- ficiency of LCN was found to be 1.5 times the commonly used nonlinear optical crystal, potassium dihydrogen phosphate (KDP). Mechanical char- acterization studies have found that the material is soft in nature, show- ing load-dependent behavior. Dielectric studies give information about the low refractive index and extinction coefficient at a high frequency, thus showing the films to have good optical quality. Thus, with such fine properties, LCN is anticipated to be a promising candidate for integrated photonic and electro-optic devices.