# Dynamics of Frenkel Excitons in Pentacene

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## Abstract

**:**

## 1. Introduction

## 2. Model Hamiltonian and Pentacene Structure

## 3. Dispersion of Noninteracting Excitons

## 4. Perturbative Corrections

## 5. Discussion

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Schematic presentation of the pentacene lattice. A pair of exchange integrals corresponds to each set of the lattice vectors $\{\mathit{a},-\mathit{a}\}$, $\{\mathit{b},-\mathit{b}\}$, and $\{\frac{\mathit{a}+\mathit{b}}{2},\frac{-\mathit{a}+\mathit{b}}{2},-\frac{\mathit{a}+\mathit{b}}{2},-\frac{-\mathit{a}+\mathit{b}}{2}\}$ (see the text).

**Figure 2.**Exciton dispersion along the $\left(100\right)$ direction. Experimental data are taken from Reference [3]. The theoretical curve is obtained for: $\Delta =1.83\phantom{\rule{3.33333pt}{0ex}}\mathrm{eV}$ [33], ${I}_{1}^{x}=5.7\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$ and ${I}_{3}^{x}=23.4\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$.

**Figure 8.**Exciton dispersion along the $\left(100\right)$ direction. Experimental data are taken from Reference [10]. The theoretical curve is obtained for: $\Delta =1.90\phantom{\rule{3.33333pt}{0ex}}\mathrm{eV}$ [33], ${I}_{1}^{x}=5.7\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$, ${I}_{2}^{x}=3.4\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$ and ${I}_{3}^{x}=23.4\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$.

**Figure 9.**Exciton dispersion along the $\left(110\right)$ direction. Experimental data are taken from Reference [10]. The theoretical curve is obtained for: $\Delta =1.90\phantom{\rule{3.33333pt}{0ex}}\mathrm{eV}$ [33], ${I}_{1}^{x}=5.7\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$, ${I}_{2}^{x}=3.4\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$ and ${I}_{3}^{x}=23.4\phantom{\rule{3.33333pt}{0ex}}\mathrm{meV}$.

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**MDPI and ACS Style**

Gombar, S.; Mali, P.; Pantić, M.; Pavkov-Hrvojević, M.; Radošević, S.
Dynamics of Frenkel Excitons in Pentacene. *Materials* **2018**, *11*, 2219.
https://doi.org/10.3390/ma11112219

**AMA Style**

Gombar S, Mali P, Pantić M, Pavkov-Hrvojević M, Radošević S.
Dynamics of Frenkel Excitons in Pentacene. *Materials*. 2018; 11(11):2219.
https://doi.org/10.3390/ma11112219

**Chicago/Turabian Style**

Gombar, Sonja, Petar Mali, Milan Pantić, Milica Pavkov-Hrvojević, and Slobodan Radošević.
2018. "Dynamics of Frenkel Excitons in Pentacene" *Materials* 11, no. 11: 2219.
https://doi.org/10.3390/ma11112219