Pyrazole based solid state emissive NLOphores with TICT characteristics: Synthesis, DFT and TDDFT studies

A series of pyrazole based D-pi-A derivatives with large stokes shift have been synthesized from 1,3-dipheny-1H-pyrazole-3-carbaldehyde by reacting with a series of active methylenes and characterized by spectroscopic analysis. The synthesized dyes show blue to red solid state emissions in the range of 441 -604 nm. All the pyrazole dyes, except dye 2.3.6.4-((1,3-dipheny-1H-pyrazole-4-yl)methylene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, display solid state emission characteristics. Experimental absorption and emission wavelengths measured for all the synthesized dyes are in good agreement with those predicted using the Time-Dependent Density Functional Theory. In this paper, the static first, second hyperpolarizability and its related properties estimated for pyrazole based push-pull dyes using B3LYP functional with 6-311G(d) basis sets. We have performed experimental calculation to determine the first hyperpolarizability using solvatochromic shift method. These dyes show high first hyperpolarizability in the range of 39.96-296.35 x 10(-30) esu by theoretical method and 35.8 -302 x 10(-30) esu by solvatochromic shift method. (C) 2015 Elsevier Ltd. All rights reserved.