Solvent effects on optical properties of 26DCzPPy material

Abstract

Solvent effects on changes in optical and some electrical properties of 26DCzPPy WOLEDs material were studied. The highest optical conductance of the material was obtained at the DCM solvent, while the lowest optical conductance of the material was obtained at the THF solvent. In addition, it was found that the electrical conductance of the 26DCzPPy is higher than the optical conductance of the material. At 340 nm wavelength, the refractive index peak value of the material varied from 2.8 to 3.5. The single oscillator energy of 26DCzPPy was found to be 2.727 eV and dispersion energy of the material was found to be 0.207 eV for THF solvent. In addition, (αj) molar polarizability of the material was calculated as 5.909×10-24 cm-3 using the theory of Clausius Mossotti local field polarizability. It was observed that the contrast value of 26DCzPPy material was changing with various solvents. It was found that the refraction angle of our material decreases from ∼40 ° to ∼15 ° for all solvents at the range of 3.48–3.62 eV. The highest optical band gap (direct-allowed) energy of the 26DCzPPy material was found at CHCI3, while the lowest optical band gap (direct-allowed) energy of the 26DCzPPy material was found at THF solvent. The molar extinction coefficient peak values varied from ∼1.3×10-5 to ∼1.8×10-5 L mol-1cm-1 for CHCI3, DCM, and THF solvents, respectively, showing a decreasing trend for various solvents. As a result; crucial optical and some electrical properties of 26DCzPPy material were obtained and discussed depending on the different solvent.