Solvation effects on the excitation dynamics, structural and photorelaxation, quantum chemical investigation, and photophysical properties of 2D p-expanded quinoidal terthiophene (2DQTTs): Outlook from Ab-initio calculations

Abstract

All dyes have different degrees of absorption. The present study delves into the intricate interplay between solvation and the photophysical behaviors of 2D p-expanded quinoidal terthiophene (2DQTT) dye compounds represented as A3, A4, and A5. In this study, a comprehensive investigation is presented, elucidating how solvation impacts excitation dynamics, ground and excited state geometry, photophysical characteristics. and photorelaxation dynamics of 2DQTTs. The energy gap data shows that the energies of the compounds increased in polar mediums and were greater for compound A3 which had ΔE values of 3.5227 eV in water, and 3.5225 eV in DMSO while compound A5 had the highest ΔE in all phases, with a ΔE value of 3.5453 eV in EtOH. Relaxation of the compounds leads to changes in the bonds and structural conformation of the 2D P-expanded quinoidal terthiophene (2DQTT) compounds as the compounds de-excite back to a lower energy level, and the photon causes a change in structural bonding (Stokes shift) in the heteroatoms which was taken into consideration. This manuscript not only advances our fundamental understanding of the interactions between solvation and molecular structure but also provides valuable insights into optimizing the performance of 2DQTT in optoelectronic devices as the compounds display a high absorption band in all phases, especially in water medial with compound A3, A4 and A5 recording absorbances of 785.32 nm, 787.13 nm, and 786.78 nm respectively, a high light harvesting efficiency LHE, great electron exciton energy and an injecting capacity (ΔGinject) greater than 0.20 eV in all phases. This work contributes significantly to the design and application of novel materials for next-generation optoelectronic technologies hence we hope that experimental research tests the studied compound towards the mentioned application.