Insights into the vibration coupling effects on reorganization energy in π-isoelectronic frameworks

Abstract

A π-isoelectronic framework denotes a category of chemical compounds or molecular structures where specific elements are arranged to share an identical count of π electrons. It presents a unique and exclusive avenue for investigating the dynamics of charge carriers at the molecular level within organic semiconductors. Despite the high similarities in molecular structure, geometry, and electron distribution among π-isoelectronic frameworks, there exists a noteworthy divergence in their reorganization energy under certain conditions. This anomaly poses a challenge to established theories in organic semiconductor science, fueling a profound interest among scientists to decipher the underlying mechanisms governing reorganization energy. Our research undertakes a comparative study of the contribution of vibrational coupling to the reorganization energy within both zigzag and armchair groups of isoelectronic frameworks. It also uncovers the peculiar odd–even effect of vibrational modes on hole reorganization energy, particularly when heteroatoms are introduced. This study offers a distinct perspective on comprehending the origins of conductivity in organic semiconductors, ushering in fresh insights into the intricate interplay between vibrational modes, reorganization energy, conductivity, and the performance of organic devices. Consequently, it furnishes a comprehensive understanding of reorganization energy through the lens of vibrational coupling and provides insights into the conductivity of organic semiconductors.