"In the first phase, the optimization of a set of force field parameters was carried out.
Due to large number of available force fields we omitted any force field refinements. Instead, we set another alternative goal to assess available force fields and name three computer models (one for the sugars, the ionic liquid, and water) that work reliably well in combination.
Due to the abundance of force fields, and the scarcity of available (useful) experimental data this part took longer than expected. In fact, some experimental data was of little use, and in the end, we were left with a limited range of data. This data was completed with high precision (quantum) DFT calculations. This part was done in collaboration with Dr. Elixabete Rezabal (University of the Basque Country, Spain) who is an expert in conducting DFT calculations on solutions.
In second phase, the dissolution of crystalline β-D-glucose in IL and water was studied.
We performed simulations where we applied position restraint to all glucose molecules except for one, either at the middle or at the corner of an edge (those that we found to be most prone to get dissolved). We tested different potential collective variables as order parameter describing the dissolution and found that the number of H-bonds both with the other sugars and solvent molecules works best. Based on the generated dissolution trajectories further “reactive” trajectories were generated using the PyRETIS python library to carry out Transition Path Sampling calculations.
The analysis of the results is still being carried out, and we expect to finish this analysis and proposing a dissolution mechanism by Spring.
The dissolution of cellobiose, in a very similar manner is still being studied. We found that attacks on the glycosidic bond and breaking its stabilizing H-bonds (leading to conformational changes) is crucial for increasing the molecule's flexibility and hence also the probability of being exposed to further ""dissolution attacks"". In the case of both sugar molecules (glucose and cellobiose) we observed that the CH2OH group is the most likely to lose its H-bonds with other sugar molecules.
During the execution of the project we concluded that a restructuring of the tasks was sensible in order to reach a more complete picture.
Accordingly, we decided to first understand the dissolution mechanisms and to tackle the recrystallization in a later stage.
I took part in the following dissemination activities:
-Scientific conferences:
-Liquid matter conference 2017, Ljubljana, Slovenia
-European molecular liquids group (EMLG/JMLG) conference 2017, Vienna, Austria
-11th Conference on Colloid Chemistry, Eger, Hungary
-10th Liblice Conference on Statistical Mechanics, Srní, Czech Republic
-EMLG/JMLG Conference 2018, Nagoya, Japan
-Dissemination to the general public:
-“Lange Nacht der Forschung”, long night of the research: Nation-wide science night2028program series in Austria for the general public, especially kids
-“Apáczai Napok” Week of external presentations’ series at the Apáczai high school2028 (my former high school in Budapest, Hungary)"
