Modulating electronic properties of dinitrosoarene polymers

0556654 - ÚOCHB 2023 RIV GB eng J - Journal Article
Matasovic, Lujo - Panic, B. - Bubaš, M. - Vančik, H. - Biljan, I. - Rončević, Igor
Modulating electronic properties of dinitrosoarene polymers.
Journal of Materials Chemistry C. Roč. 10, č. 14 (2022), s. 5433-5446. ISSN 2050-7526. E-ISSN 2050-7534
Research Infrastructure: e-INFRA CZ - 90140
Institutional support: RVO:61388963
Keywords : total energy calculations * organic semiconductors * GW calculations
OECD category: Organic chemistry
Impact factor: 6.4, year: 2022
Method of publishing: Limited access
https://doi.org/10.1039/D2TC00760F

Using the dinitrosobenzene polymer (1) as a model, we explore how the electronic, transport, and optical properties of a conjugated organic semiconductor can be modulated. Combining computational and experimental tools, we explore the effects of solid-state packing, backbone torsion, surface adsorption, the conjugation in the aromatic core, and substituents. The band gap (E-g) and optical spectrum of 1 are calculated using both GW-BSE with zero-gap renormalization (ZGR) and hybrid TD-DFT, with the former method predicting a value (2.41 eV) in excellent agreement with our diffuse reflectance spectroscopy measurements (2.39 eV). Using GW-BSE-ZGR, changes occurring upon solid-state packing are separated into a contribution arising from (i) the change in the torsional angle and (ii) the change in the screened Coulombic interaction, which strongly affects the exciton binding energies. Comprehensive hybrid TD-DFT calculations find that the effects of substituents on E-g and on transport properties can mostly be explained through changes in the torsional angle theta, and predict a linear dependence between theta and E-g. Extending the conjugation in the aromatic core is found to enhance transport properties and narrow E-g, identifying future synthetic targets. Atomic force microscopy and spectroscopic ellipsometry are used to study 1 adsorbed to a (111) gold surface (1@Au), with the latter method showing a significant narrowing of the band gap to 0.68 eV, in good agreement with TD-DFT predictions.
Permanent Link: http://hdl.handle.net/11104/0331166