Laboratory for Computational Molecular Design, École polytechnique fédérale de Lausanne, Switzerland
Vendredi 21 décembre à 14h (salle Magat) :
“Manipulating Energy through Space in Molecules and Materials”
Résumé
Chemical stability and reactivity are habitually expressed through various energetic measures, such as bond, reaction or interaction energies. In this talk we demonstrate how these quantities can be manipulated through space, i.e. without directly altering the immediate chemical surroundings of the reacting or interacting centres. Specifically, in the first part of this presentation unconventional stabilisation of the delocalised systems with external electric fields will be discussed.[1] Highly polarisable species, such as delocalised radicals and transition states of many chemical reactions, can be significantly stabilised (or destabilised) by electrostatic effects. In some species stabilisation is observed independent of the relative orientation of the EEF, thus emphasising the counter- intuitive non-directional nature of this polar effect. In the second part of the talk we will discuss another type of electrostatic effect – charge penetration – that arises at short range between the nuclei of one species and the diffuse electron cloud of another. In a number of organic semiconductor materials, this interaction mirrors the strength of energetic and electronic communication between the neighbour molecules, and thus can be harnessed to achieve assemblies with improved stability and conductance.[2]
Références
[1] (a) Gryn’ova, Marshall, Blanksby, Coote, Nat. Chem. 2013, 5, 474. (b) Gryn’ova, Coote, J. Amer. Chem. Soc. 2013, 135, 15392. (c) Gryn’ova, Coote, Aust. J. Chem. 2017, 70, 367.
[2] (a) Gryn’ova, Corminboeuf, J. Phys. Chem. Lett. 2016, 7, 5198. (b) Gryn’ova, Corminboeuf, J. Phys. Chem. Lett. 2018, 9, 2298. (c) Gryn’ova, Corminboeuf, Beilstein J. Org. Chem. 2018, 14, 1482.
