The objective of this thesis around the metalla bisdicarbollides family, ionic clusters of boron and carbon around a transition metal and considered as a strong inorganic acid, is threefold: i) to model in describing a lateral equation of state their self-association via weak interactions  that governs their aggregation in a monomolecular film or in spherical aggregates. ii) to create some nanosensors by the control their deposition on silicon substrates in order to master the electronic and ionic transport over 2 and 3-dimentionnal supramolecular structures. iii) to use the complexation properties of these molecules in a biochemical approach.

These three objectives are based on the skills of the team and a collaboration with Pr. Teixidor and our various recent studies that describe the richness and originality of the formation of lyotropic liquid-crystalline phases obtained with these atypical ions (Bauduin et al. Angew. Chem Int. Ed 2011 and 2013). In collaboration with the laboratory of theory at ICSM (LMCT), it is possible to take into account the specific interactions between these ions in their aggregation process in order to quantify the forces involved that can stabilize different structures encountered, an approach already used (with the LMCT) to understand the phenomena of ionic complexation (Müller et al, JPC B 2013; Bappaditya et al, JPC C, 2015). Some experimental studies such as Raman spectroscopy or high resolution infrared spectroscopy using synchrotron radiation and by controlling precisely the activity of water are needed to provide all the elements required for modelling (1st objective).
The second objective will be based on understanding of the interactions between dicarbolide/dicarbolide and dicarbolide/cationic surfactant to control the deposition of these ions on silicon substrate to form crystallized layers (De Viguerie et al, CrysEngComm 2012) and to emphasize the (nonlinear) optical, magnetic and electrical properties, particularly advantageous for this type of system, according to the degree of oxidation of the metallic cation. The last part will be more prospective and will be related to the ionic transfer through biological membrane in model systems such as phospholipids-based liposomes and in living cells. This last part will be developed in collaboration with other French and foreign laboratories (ENS-Lyon, CEA-Saclay and Cardiff university).

Laboratory : L2IA (Olivier Diat)
Thesis supervisor : Olivier Diat
Person to contact : Olivier Diat et Pierre Bauduin (olivier.diat@cea.fr; pierre.bauduin@cea.fr)
Starting date : october 2016
Annoncement reference : SL-DSM-16-0105