NLOphoric and solid state emissive BODIPY dyes containing N-phenylcarbazole core at meso position - Synthesis, photophysical properties of and DFT studies

Two boron-dipyrromethene dyes with N-phenylcarbazole core at meso position were prepared and characterized. They show small Stokes shifts (15-20 nm), high molar extinction coefficient and high quantum yield. Their photophysical properties were compared with the known meso aryl, 4-aminophenyl, N,N-dimethylaniline and N-butylcarbzole boron-dipyrromethene dyes. The bulky nature of N-phenylcarbazole leads to an increase in molar absorptivity and quantum yield. The Catalan solvent parameters are found to be the suitable for defining the solvatochromic absorption and emission properties. Confocal laser scanning microscopy showed solid-state fluorescence. Density Functional Theory is used to determine the static first hyperpolarizability (βο) and its components (μ, α0, Δα, and γ) using B3LYP/6-31G(d) at ground state and excited state in different polarity solvent. The geometries of the dyes were optimized by using B3LYP/6-31G(d) and their electronic excitation properties were estimated using time dependent density functional theory.