17 Feb 2024
Job Information
- Organisation/Company
CNRS- Department
PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX- Research Field
Chemistry » Physical chemistry
Chemistry » Computational chemistry- Researcher Profile
First Stage Researcher (R1)- Country
France- Application Deadline
8 Mar 2024 - 23:59 (UTC)- Type of Contract
Temporary- Job Status
Full-time- Hours Per Week
35- Offer Starting Date
1 Oct 2024- Is the job funded through the EU Research Framework Programme?
Not funded by an EU programme- Is the Job related to staff position within a Research Infrastructure?
No
Offer Description
Phenix Laboratory, UMR 8234, Sorbonne Université
The PhD student will be part of the Electrochemistry and Ionic Liquids team
Project description
Aqueous secondary batteries based on economical, safe and environmentally friendly materials have the potential to impact the stationary energy storage market (more than 32Bn$ by 2030). One direction to improve the performance of such batteries is to develop new high-performance and more stable redox electrolytes. This PhD project has the objective to take a first step in this direction by performing molecular computation on a database of nitroxide molecules (Figure 1) that will be used to define some molecular descriptors allowing to select the most promising redox active species for aqueous battery applications. Such descriptors will be subsequently employed by the PhD student to perform a high-throughput analysis of nitroxide derivatives to identify the most promising candidates to synthesize. A first natural descriptor is the redox potential which can be computed using electronic structure methods, such as the electronic density functional theory. However, due to a prohibitive computational time, most studies attempting to perform a systematic study of redox molecules, such as quinones and nitroxides disregard the role of the solvent. Since redox active specie stability is a key parameter the practical design of a competitive redox flow battery, we believe it is essential to keep a faithful description of the solvent. It is also mandatory to keep the computation cost tractable which is why we will resort to molecular density functional theory (MDFT). This method allows to compute the solvation free energy and the solvation structure in water or in organic solvent within a few minutes on a standard laptop.
Considered descriptors are solvation free energy, coordination number which can be used to assess the number of hydrogen bonds, redox potentials and partition coefficient between water and an organic solvent. We will also compute the reorganization free energies of the active species following a procedure we recently published [1]. Reorganization free energies can be related to rate constants through activated complex theory. Calculation of the redox potentials requires a computation of the ground state energies of both oxidation states in the presence of the solvent which can be done using the recently published hybrid quantum mechanics MDFT method [2]. Since it requires performing several quantum calculations, the QM/MDFT approach is more computationally demanding, but it remains several orders of magnitude faster than a full QM description.
MDFT is a flavor of classical DFT designed to study the solvation of chemically complexed solutes in a molecular solvent. The solvent is described by a density field. Due to the presence of the solute molecule, represented by an external potential acting on the solvent, this density is perturbed and become inhomogeneous. The DFT ansatz guarantee the existence of a functional of the solvent density that reaches its minimum for the equilibrium solvent density and that is equal to the solvation free energy at this minimum. This theory has proved to be competitive with respect to state-of-the-art simulation techniques for the description of the solvation of a wide range of solutes into molecular solvent such as water and acetonitrile.
[1] TY. Hsu, R. Berthin, A. Serva, K. Reeves, M. Salanne, and G. Jeanmairet. The Journal of Chemical Physics, 157(9) 2022
[2] G. Jeanmairet, M. Levesque, and D. Borgis. Journal of Chemical Theory and Computation, 16(11) 2020
Requirements
- Research Field
- Chemistry
- Education Level
- Master Degree or equivalent
- Research Field
- Chemistry
- Education Level
- Master Degree or equivalent
- Languages
- FRENCH
- Level
- Basic
- Research Field
- Chemistry » Physical chemistry
- Years of Research Experience
- None
- Research Field
- Chemistry » Computational chemistry
- Years of Research Experience
- None
Additional Information
- Website for additional job details
https://emploi.cnrs.fr/Offres/Doctorant/UMR8234-GUIJEA-001/Default.aspx
Work Location(s)
- Number of offers available
- 1
- Company/Institute
- PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX
- Country
- France
- City
- PARIS 05
- Geofield
Where to apply
- Website
https://emploi.cnrs.fr/Candidat/Offre/UMR8234-GUIJEA-001/Candidater.aspx
Contact
- City
PARIS 05- Website
http://www.phenix.cnrs.fr
STATUS: EXPIRED
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