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arXiv · 1904.01881

Optoelectronic properties of one-dimensional molecular chains simulated by a tight-binding model

Q. Chen·J. Chang·L. Ma·C. Li·L. Duan·X. Ji·J. Zhang·W. Wu·H. Wang
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Abstract

Studying optical properties of organic materials is important due to the rapid development of organic light-emitting diodes, solar cells, and photon detectors. Here for the first time we have performed tight-binding calculations for singlet excitons, in combination with first-principles calculations of the excited states in molecular dimers, to describe the optical properties of a zinc-phthalocyanine one-dimensional molecular chain. We have included the intra-molecule and charge-transfer excitations and the coupling between them. Our calculations have successfully interpreted a body of experimental UV-Vis optical spectra of transition-metal phthalocyanines. Compared with the previous ab initio calculations for a molecular dimer, the optical absorptions at the split peaks of the Q-bands can be comparable, which indicates the importance of the coupling between the intra-molecular and charge-transfer excitons.

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Q. Chen, J. Chang, L. Ma, C. Li, L. Duan, X. Ji, J. Zhang, W. Wu, H. Wang. 2019-04-03. Optoelectronic properties of one-dimensional molecular chains simulated by a tight-binding model. https://doi.org/10.1063/5.0030776

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