Towards better understanding of photophysical properties of rhenium(I) tricarbonyl complexes with terpy-like ligands

Magdalena Małecka; Barbara Machura; Anna Świtlicka; Sonia Kotowicz; Grażyna Szafraniec-Gorol; Mariola Siwy; Marcin Szalkowski; Sebastian Maćkowski; Ewa Schab-Balcerzak

doi:10.1016/j.saa.2020.118124

Towards better understanding of photophysical properties of rhenium(I) tricarbonyl complexes with terpy-like ligands

Spectrochim Acta A Mol Biomol Spectrosc. 2020 Apr 15:231:118124. doi: 10.1016/j.saa.2020.118124. Epub 2020 Feb 6.

Authors

Magdalena Małecka¹, Barbara Machura², Anna Świtlicka¹, Sonia Kotowicz¹, Grażyna Szafraniec-Gorol¹, Mariola Siwy³, Marcin Szalkowski⁴, Sebastian Maćkowski⁴, Ewa Schab-Balcerzak⁵

Affiliations

¹ Institute of Chemistry, University of Silesia, 9th Szkolna Street, 40006 Katowice, Poland.
² Institute of Chemistry, University of Silesia, 9th Szkolna Street, 40006 Katowice, Poland. Electronic address: barbara.machura@us.edu.pl.
³ Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Sklodowska Str., 41-819 Zabrze, Poland.
⁴ Nanophotonics Group, Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, 5 Grudziadzka Str., 87-100 Torun, Poland.
⁵ Institute of Chemistry, University of Silesia, 9th Szkolna Street, 40006 Katowice, Poland; Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 M. Curie-Sklodowska Str., 41-819 Zabrze, Poland. Electronic address: ewa.schab-balcerzak@us.edu.pl.

PMID: 32062513
DOI: 10.1016/j.saa.2020.118124

Abstract

Series of Re(I) carbonyls complexes were designed and synthesized to explore the impact of the triimine skeleton and number of methoxy groups attached to aryl substituents on their optoelectronic and thermal properties. The chemical structures of the prepared complexes were confirmed by ¹H and ¹³C NMR spectroscopy, HR-MS, elemental anlsysis, and X-ray measurements. DSC measuremtns showed that they melted in the range of 198-325 °C. Some of them form stable molecular glasses with high glass transition temperatures (158-173 °C). Experimentally obtained optical properties were supported by DFT calculations. The UV-Vis spectra display a series of overlapping absorption bands in the range 200-350 nm, and much weaker broad band in the visible spectral region, due to intraligand and charge transfer transitions, respectively. All synthesized complexes were emissive in solution and in solid state as powder. Moreover, when applied in diodes, some of them exhibited ability for emission of light under external voltage with maximum of electroluminescence band located at 591-630 nm.

Keywords: Electroluminescence; Photoluminescence; Re(I) carbonyl; Terpy-like ligands.