Spectral, thermal and SHG studies on phase matchable organic NLO material EDMP for blue-green laser generation

1-Ethyl-2,6-dimethyl-4(1H)-pyridinone trihydrate (EDMP), is an organic crystalline material exhibiting quadratic nonlinear optical (NLO) properties, in particular, second harmonic generation (SHG) down to the ultraviolet region. The material was synthesized from two different starting materials namely 2,6-dimethyl-4-pyrone and dehydroacetic acid following two different routes. The material was characterized by FT-IR, FT-NMR and elemental analysis. The lower cutoff wavelength was found to be 280 nm in EtOH with a good optical transmittance window covering the UV–Vis–NIR region. Thermal behaviour of EDMP was studied by TG and DTA. The powder SHG efficiency was measured using a Q-switched Nd:YAG laser assembly by a modified Kurtz and Perry powder technique and its phase matching property was established.