Contributed talk

Exploring the indenofluorene diradical
Alba Millan, R. Casares, A. Martínez-Pinel, and J. M. Cuerva

Departamento de Química Orgánica, Universidad de Granada, Spain

Open-shell organic diradicals have been postulated as promising candidate molecules for spintronics. [1] In this sense, it is essential to understand the transport at the single-molecule level, and diradicals are, certainly, unexplored. In addition, having tools to modulate the singlet-triplet energy gap in a straightforward manner would be of utmost utility for real implementation of organic diradical as active components in molecular electronics.

Herein, we focus on a family of organic diradicals: the indenofluorenes (IFs) (Figure 1). This polycyclic conjugated hydrocarbon is composed by a 6-5-6-5-6 fused core which present a central quinodimethane (QDM) unit. This structural motif provides the diradical character to these structures. We have studied the single-molecule conductance through the IF core and, also, across the QDM unit, finding interesting results. In order to fine-tune the properties of IFs, we have developed a new strategy that allows the modulation of the singlet-triplet energy gap in a simple manner. [2] This strategy has been used to synthesise configurationally stable open-shell chiral diradicals. [3]

Figure 1: Our studies on indenofluorenes.

[1] Y. Tan et al., J. Am. Chem. Soc. 144, 626 (2022)
[2] R. Casares et al., J. Mat. Chem. C 10, 11775 (2022)
[3] We thank MCIN/AEI/10.13039/501100011033 (PID2021-127964NB-C22) for financial support.