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arXiv · 2005.04993

Overcoming the challenges in controlled thermal deposition of organic diradicals

Tobias Junghoefer·Nolan M. Gallagher·Kubandiran Kolanji·Erika Giangrisostomi·Ruslan Ovsyannikov·Thomas Chassé·Martin Baumgarten·Andrzej Rajca·Arrigo Calzolari·Maria Benedetta Casu
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Abstract

We have demonstrated that it is possible to evaporate diradicals in a controlled environment obtaining thin films in which the diradical character is preserved. However, evaporation represents a challenge. The presence of two radical sites makes the molecules more reactive, even in case of very stable single radicals. We have explored the parameters that play a role in this phenomenon. Bulk formation thermodynamics and delocalisation of the unpaired electrons play the major role. The higher the formation energies of the crystal, the more difficult is the evaporation of intact radicals. The larger the delocalization, the more stable is the film exposed to air. The evaporation of different radicals, also with a larger number of radical sites can be successfully addressed considering our findings.

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Tobias Junghoefer, Nolan M. Gallagher, Kubandiran Kolanji, Erika Giangrisostomi, Ruslan Ovsyannikov, Thomas Chassé, Martin Baumgarten, Andrzej Rajca, Arrigo Calzolari, Maria Benedetta Casu. 2020-05-11. Overcoming the challenges in controlled thermal deposition of organic diradicals. https://arxiv.org/abs/2005.04993

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