A chance scientific connection has led to a fruitful international collaboration. While working on her PhD project involving polyoxometalates (POMs), Dr. Laura S. Junkers (University of Copenhagen) came across a computational tool developed at ICIQ, at the group of Prof. Carles Bo: POMSimulator. Eager to understand how it worked, she arranged a research stay in Tarragona to learn directly from its creators. A few months later, Junkers has gone on to co-lead a collaborative study that brings together this computational approach with advanced experimental techniques. The work, now published in the Journal of the American Chemical Society (JACS), combines the strengths of predictive modelling and synchrotron-based X-ray scattering to better understand POM behaviour under hydrothermal conditions.
POMs are a group of versatile molecular structures that play a key role in many chemical processes, and the team has demonstrated that combining theoretical predictions with experimental data leads to a much better understanding of how POMs behave in solution, particularly under the high temperatures and pressures commonly used in hydrothermal syntheses.
Why predicting POM formation matters
Hydrothermal synthesis is a common method for producing metal oxides, which can involve the formation of POMs—tiny molecular clusters whose structure depends on factors like pH, temperature, and concentration. Controlling which POMs form under specific conditions is crucial for guiding synthesis and determining the final material’s properties, but their dynamic behaviour in solution makes this difficult to predict.
To tackle this, the team of Prof. Carles Bo expanded a previously developed computational tool, POMSimulator. Originally designed for ambient conditions, the software uses quantum chemistry methods to model how POMs behave in solution. The researchers have now extended its capabilities to reflect changes in water properties at high temperatures and pressures, making it suitable for modelling hydrothermal environments.
Synergy as a way forward
To validate their predictions, the team worked with the group of Assoc. Prof. Kirsten M. Ø. Jensen at the University of Copenhagen who carried out X-ray total scattering experiments at the MAX IV synchrotron in Sweden. Using a custom setup, they tracked the structure of molybdate solutions under hydrothermal conditions, directly matching those simulated.
The comparison showed a clear complementarity: computational models proposed likely species, while the experiments confirmed qualitative trends and revealed additional structural details. This synergy helped the researchers understand, for instance, how the crystallisation of h-MoO₃ at high temperatures and low pH is linked to the destabilisation of certain POMs.
Dr. Laura S. Junkers, sharing the first authorship of the study with Dr. Diego Garay-Ruiz, highlighted the value of this integrated approach:
“POMSimulator provided a chemically informed starting point for analysing our experimental data, while the experimental approach added nuance to the picture of POM speciation. More broadly, our study shows the added value of integrating computational and experimental methods to tackle complex chemical systems.”
Setup of the synchrotron experiment. Picture by Guilherme B. Strapasson
Towards Smarter Material Design
“Chemically informed methodologies like POMSimulator address certain limitations and hold immense potential for complementing experimental studies with additional insight into the intricate equilibria of POM speciation” added Prof. Carles Bo.
This study lays the groundwork for future research into metal-oxide formation in solution, particularly under hydrothermal conditions which pose a particular scientific challenge. By showing how simulation and experiment can inform one another, it opens up new possibilities for improving synthesis control—ultimately leading to smarter, more rational material design.
Reference publication
Uncovering Polyoxometalate Speciation in Hydrothermal Systems by Combining Computational Simulation with X-ray Total Scattering
Junkers, L. S.; Garay-Ruiz, D.; Buils, J.; Silberg, R. S.; Strapasson, G. B.; Jensen, K. M. Ø.; Bo, C
J. Am. Chem. Soc. 2025
DOI: 10.1021/jacs.5c04696
La entrada Combining computation and experiment helps predict the chemistry involved in metal-oxide formation se publicó primero en ICIQ.