Title of research project

Droplet Explosion for the analysis of MOlecular Native Structures

Postdoctoral position in the field of gas phase laser spectroscopy

Contract type Contrat (CDD) Category A Workload Fulltime

Scientific field Chimie
Physique

WorklJob Descriptionoad

Description of the offer Context : Unravelling the structures of biomolecules to predict their function is a key process to understand their behaviour in multiple biological processes. This can be achieved using the selectivity and specificity of the gas-phase spectroscopic tools. Studies on controlled and finite size systems allow for comparison with theoretical predictions, with a high level of achievement. Nevertheless, these experiments in which the environment is removed to work on isolated species make difficult any extrapolation to the condensed phase. To overcome this difficulty, our strategy is to develop an innovative gas phase ion source which will allow to interrogate micro-hydration processes. This source, unique in France, is based on laser desorption of liquid microdroplets directly under vacuum [1]. Objectives : Within the framework of the "DEMONS" ANR project, the candidate will perform the experimental investigation of the desorption phenomena induced by the interaction of an infrared laser pulse (tuned to water absorption band) with a liquid water microdroplet (50 micrometers diameter) under vacuum. Underlying mechanisms are poorly undestood (supercritical phase transition, supersonic shock wave…) and the way energy is deposited into the microdroplet strongly influences the nature and quantity of desorbed species (biomolecules into the droplet). In a second step, the gas phase source will be coupled to a cryogenically cooled ion trap to get structural information on the desorbed species by performing infra-red multiphoton dissociation spectroscopic studies. [1] Badri et al. Rev. Sci. Instrum. (2025) 109.

Field of research Molecular physics, gas phase Chemical physics

Skills Mass spectrometry, Infrared spectroscopy, vacuum techniques

Knowledge

Work environment

Location Villetaneuse

Laboratory Laboratoire de Physique des Lasers

Degree level

Degree required PhD in physics or in chemistry obtained in 2024 or after

Experience required Proficiency in one or more gas-phase experimental techniques (mass spectrometry, laser spectroscopy, ion trap) is expected.

Additionnal information

Start date 03 02 26

Job Type Contrat (CDD)

Contract duration 1 an

Application deadline 01 30 26

Deadline passed

Back to list Fermer