Project Description

Chemical reactions may show up to 6 orders of magnitude rate acceleration in microdroplets of rapidly evaporating solvents. The underlying mechanisms that determine whether acceleration happens for a specific reaction and a specific solvent, how large it will be, and which aspects control the magnitude are not yet understood. These mechanisms are urgently needed as the basis of microdroplet-based synthetic technologies and for maximizing rates of acceleration, especially for reaction classes relevant in medicinal chemistry.
Our initial quantum mechanical calculations show that the orientation of reactants relative to the solvent/vacuum interface has immense impact on the molecular energy. Depending on the relative energy change of reactants and transition states in the proximity of the droplet surface, chemical reactions can gain significant accelerations in microdroplets.
Nonetheless, these initial calculations were based on state-of-the-art density functional theory models with periodic boundary conditions. In this project code will be developed for chemical reactions in microdroplets including irregular, open boundaries – such as liquid/vacuum interfaces. This project will use established NEGF calculations tailored to simulate reaction acceleration mechanisms and to explain and control physical and chemical aspects that 1) determine the reaction acceleration factor and 2) allow control of the acceleration in experiment.

Start Date 

mid-March 2020

Postdoc Qualifications 

Experience in density functional theory, molecular dynamics and (ideally) quantum transport calculations
Experience with chemical reactions and their computational predictions will be helpful. 
Experience with using Linux, compute clusters and basic scripting skills will ease the project start. 
Excellent communication skills will be needed to integrate into a highly diverse team.

Co-advisors

Tillmann Kubis
tkubis@purdue.edu
School for Electrical and Computer Engineering
group.tkubis.com

R. Graham Cooks
cooks@purdue.edu
Department of Chemistry
aston.chem.purdue.edu

References 

X. Yan, R. M. Bain, and R. G. Cooks, Organic Reactions in Microdroplets: Reaction Acceleration Revealed by Mass Spectrometry, Angew. Chem. Int. Ed. 55, 12960 (2016)

Y. He, Y. Wang, G. Klimeck, and T. Kubis, Non-equilibrium Green's Functions Method: Non-trivial and Disordered Leads, Appl. Phys. Lett. 105, 213502 (2014)

T. Kubis, Nonequilibrium Green's Functions: Reliably Predicting Chemical Reactions, https://nanohub.org/resources/26040