Synthesis and Characterization of Pyrano[3,2-C]Chromene Derivatives: Exploring Their Optoelectronic and Charge Transport Properties by First-Principles Approach

With the aim to enhance the charge transport, optoelectronic and semiconducting properties various multifunctional pyrano[3,2-c]chromene derivatives were synthesized and characterized. To shed light on the various properties of interests, the ground state geometries were optimized by Density Functional Theory (DFT). The effect of different substituents, e.g., thiophen-2-yl, 5-bromothiophen-2-yl, 1H-indol-3-yl, pyridin-3-yl, and benzo[d][1,3]dioxol-5-yl was studied on the structural stability, electronic properties, and absorption wavelengths by DFT and Time-Domain DFT (TDDFT). The experimental excitation energies were successfully reproduced at TD-PBE/6-31G** level in DMSO. The electron injection barrier, ionization potential, electron affinity, and reorganization energies for hole and electron were calculated and compared systematically. The smaller electron reorganization energies of pyrano[3,2-c]chromene derivatives except indole substituted one is illuminating that these materials would be efficient to be used in n-type semiconductor devices.