Effect of crystallization on the electronic and optical properties of archetypical porphyrins

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2020-02-21

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Malcıoğlu, Osman Barış
Bockstedte, Michel

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Thin porphyrin films as employed in modern optical devices or photovoltaic applications show deviating electronic and optical properties from the gasphase species. Any understanding of the physical origin may pave way to a specific engineering of these properties via ligand or substituent control. Here we investigate the impact of crystallization of prototypical porphyrins on the electronic levels and optical properties in the framework of density functional theory and many-body perturbation theory. Crystallization substantially shrinks the HOMO-LUMO gap based on polarization effects. We find a shift of the HOMO to higher energy is consistent with recent experiment of MgTPP multilayer film on Ag (100) [A. Classen et al., Phys. Rev. B, 2017, 95, 115414]. Calculated excitation spectra demonstrate a significant redshift of excitation bands except for the Q bands. These lowest excitation bands, in stark contrast to the strong HOMO-LUMO gap renormalization, remain essentially the same as in the gas phase. Our work underlines the possibility of band-gap engineering via ligand-controlled modification of the polarizability.

Subject Keywords

Physical and Theoretical Chemistry, General Physics and Astronomy

URI

https://hdl.handle.net/11511/43164

Journal

PHYSICAL CHEMISTRY CHEMICAL PHYSICS

DOI

https://doi.org/10.1039/c9cp06040e

Collections

Department of Physics, Article

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Citation Formats

O. B. Malcıoğlu and M. Bockstedte, “Effect of crystallization on the electronic and optical properties of archetypical porphyrins,” PHYSICAL CHEMISTRY CHEMICAL PHYSICS, pp. 3825–3830, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43164.