A Computational Study of Optoelectronic and Charge Transport Properties of Purine Nucleobases Dinucleotides Compounds

Optoelectronic and charge transport properties of eight novel compounds are presented in this work. Density functional theory B3LYP was utilized to optimize all structures while time-dependent density functional theory was utilized for vertical excitation characteristics. Gas and solvent phases (water, THF, and DCM) were evaluated to gain insight on solid-state and solution processed devices. While the solvent phases enhanced most of the charge transport properties, there was seen a blue-shift in their absorption wavelengths. However, C2, C4, C6, and C8 in THF absorption maxima were the highest and similar to those of the gas phase (605-652 nm). Extension of the polymer size decreased the HOMO-LUMO gap energy with C7 having the lowest energy gap in the gas phase. Although tuning the properties in optoelectronic devices is challenging, these findings will assist with the design of higher quality materials that could surpass the quality of inorganic devices.