Modeling photonastic materials: from the molecular to the mesoscopic scale. – PHOTONASTIC

Development of a versatile methodological strategy based on a bottom-up multiscale approach :
- quantum chemistry
- classical Molecular Dynamics simulations (STAMP code)
- coarse-grained methods

In the PHOTONASTIC project, we will be interested in modeling the processes ranging from the molecular scale to the 100 nm-scale and from the ps to the µs time scale.

Understanding the parameters at the molecular and supramolecular scales that influence the behavior of a bio-inspired polymeric photoactuators will enable a breakthrough in optimizing the photonastic performances of a material.

Le Bras, L.; Lemarchand, C.; Aloïse, S.; Adamo, C.; Pineau, N.; Perrier, A. J. Chem. Theory Comput. 2020, 16 (11), 7017–7032. doi.org/10.1021/acs.jctc.0c00762.

Photonastic materials convert light energy into mechanical energy and are the subject of pre-determined and repeatable deformations in response to light stimulus. This project aims at identifying the key parameters at the molecular and supramolecular scales involved in the mechanical response of a photoresponsive thin film made of photochromic molecules embedded in a polymer matrix. The challenge is to rationalize the multiscale mechanisms underlying these phenomena, namely (1) the ultrafast photoreaction at the molecular level, (2) the momentum transfer to the surrounding matrix, and (3) the long-term polymer relaxation which yields the macroscopic deformation. To this purpose, we propose to develop a versatile methodological strategy based on a bottom-up multiscale approach (quantum chemistry, classical molecular dynamics and coarse-grained methods), in order to participate to the in silico design of photonastic materials with light-to-mechanical energy conversion capabilities.