News

The fascinating complexity of aqueous acid catalysis in nanoconfinement

Prof. Veronique Van Speybroeck’s research group, embedded in the Center for Molecular Modeling, in collaboration with the groups of Prof. Bert Sels (Center for Sustainable Catalysis and Engineering, KU Leuven) and Prof. Bert Maes (Organic Synthesis Division, Department of Chemistry, University of Antwerp), has provided new insights into the complex behavior of acid catalysis in nanoconfined environments.

Aqueous acid catalysis involves the acceleration of chemical reactions in the presence of solvated protons, typically existing as hydronium ions (H3O+). In bulk liquid water, these hydronium ions are fully solvated, meaning they are surrounded and stabilized by water molecules. This is the case, for example, in a glass of lemon juice, which contains citric acid. However, acid catalysis can also occur in solid acid catalysts like zeolites. Zeolites can be thought of as sponges with pores just large enough to accommodate small molecules. When hydronium ions are confined within these pores, they are no longer fully solvated by water. Instead, they are under-coordinated, meaning they are not entirely surrounded by water molecules. This change in their coordination state significantly alters their catalytic properties, making them more active in promoting certain reactions.

The study primarily focuses on the O-demethylation of guaiacol, which involves the removal of its methyl group (-CH3), resulting in the formation of catechol and methanol. This reaction is of great significance in the context of biorefinery, a forward-looking industrial process in which biomass waste (such as wood scraps, straws, and grass) is converted into building blocks for the chemical industry. These chemicals, currently derived from oil refining, are essential for the production of a wide range of everyday goods, from plastics to pharmaceuticals, to serve society’s needs.

Through a combined theoretical and experimental investigation of the guaiacol O-demethylation reaction, the researchers discovered that hydronium ions confined within small spaces are more active as catalysts than those in bulk water. This increased catalytic activity is attributed to a combination of factors: the undercoordination of the hydronium ions and the spatial organization of the reactants in relation to the catalyst. While the former is less dependent on the type of zeolite used, the latter is influenced by both the zeolite’s framework topology and the amount of water present.

These fundamental findings offer valuable insights into the atomistic mechanisms at play and pave the way for the rational design of more efficient catalysts for biomass conversion reactions, to make the transition from a society based on fossil to renewable and recycled carbon.

The study, now published in Nature Catalysis, is born within the collaborative Excellence of Science Project Biofact (https://www.biofact.be), promoting the development of a complete biorefinery to convert wood in value-added chemicals.

The article can be read at the publisher’s website: https://doi.org/10.1038/s41929-024-01282-6

CMM authors: Massimo Bocus, Elias Van den Broeck, Louis Vanduyfhuys, Veronique Van Speybroeck

FWO-funded Ph.D. positions on modelling amorphous zeolitic imidazolate frameworks using in silico nuclear magnetic resonance spectroscopy

 

The Rogge group, embedded within the multidisciplinary Center for Molecular Modeling (molmod.ugent.be) at Ghent University, Belgium, is looking for two highly motivated Ph.D. researchers to perform state-of-the-art computational research in functional materials design. The Ph.D. candidates will develop an integrated workflow combining state-of-the-art machine-learning potentials and in silico nuclear magnetic resonance spectroscopy to identify and characterise the amorphous states in zeolitic imidazolate frameworks. This requires training a ZIF-transcending machine-learning potential and determining the features necessary to fingerprint different amorphous states in zeolitic imidazolate frameworks, which in turn will help in understanding how amorphous states nucleate and grow in these functional materials. Answering these questions is vital to understanding how zeolitic imidazolate frameworks can be adopted in innovative applications.

These positions fit within a recent fundamental research project awarded to prof Sven M. J. Rogge by the Research Foundation – Flanders (FWO). We especially welcome candidates with a strong track record who are – or may become – eligible to apply for a prestigious Ph.D. fellowship at our national funding agency or wish to prepare for a European fellowship.

More info about the project

Amorphous zeolitic imidazolate frameworks (ZIFs) are designable nanoporous metamaterials demonstrating a vast capacity for functional stimuli-responsiveness, high mechanical robustness, and large-scale processibility surpassing their crystalline counterparts. Ideally, structure-function relationships would help navigate this huge ZIF design space, just as for crystalline materials. Yet, their lack of long-range structural order makes identifying these amorphous ZIFs’ structures highly challenging.

In this project, we aim to make a major leap forward by developing two in silico methodologies and combining them in an integrated and generally applicable workflow. First, we will train a ZIF-transcending machine-learning potential to model the interatomic interactions accurately. Just like ab initio methods, this MLP will be able to reproduce the experimentally observed amorphisation under heating and pressurisation, but at a substantially lower computational cost. Second, we will develop an in silico nuclear magnetic resonance (NMR) workflow to fingerprint the local amorphous structure of ZIFs and store these fingerprints in an NMR library. This library, in turn, will be adopted to locally map the ZIF structure onto distinct ZIF states.

By combining both methodologies, we aim (i) to shed light on the nucleation and growth of amorphous states upon heating and pressurising crystalline ZIFs and (ii) to derive structure-function relationships for amorphous ZIFs and enable their functional design.

Don't hesitate to contact prof Rogge (Sven.Rogge@UGent.be) for informal inquiries or more information.

More info about the CMM                        

The CMM groups about 40 researchers from the Faculty of Science and the Faculty of Engineering and Architecture at Ghent University with molecular modelling interests. It is unique in the university as it clusters computational researchers with various backgrounds, from multiple departments and faculties. The CMM aims to model molecules, materials & processes at the nanoscale by bringing together physicists, chemists, and (bio-)engineers while stimulating collaborations across disciplines. This multidisciplinary collaborative mission is the DNA of the CMM and is crucial in achieving scientific excellence in molecular modelling.

The CMM focuses on frontier research in six primary areas: computational material research on the nanoscale, model development, spectroscopy, many-particle physics, chemical kinetics in nanoporous materials, and bio-organic & organic chemistry. Our research is performed within a strong network of partners at Ghent University and at an (inter)national level. To pursue excellence, we strongly stimulate interactions between the various researchers in our team and our vast network of national and international partners. The prospective candidates will join a strongly connected research team and collaborate with national and international academic partners. The research of the CMM is internationally regarded to be at the forefront of its field.

Who are we looking for?

We are looking for highly motivated Ph.D. candidates with: 

  • a Master’s degree or an international equivalent in physical chemistry, chemical physics, condensed matter physics, statistical physics, theoretical physics, or a related field obtained before your first working day at the CMM.
  • demonstrated experience with coding (Python, C, etc.) and quantum chemistry software (Gaussian, VASP, CP2K, etc.) or force-field-based simulations is an advantage;
  • a strong interest in molecular modelling;
  • excellent research and scientific writing skills;
  • perseverance and an independent, proactive working style;
  • the willingness to look beyond the borders of your discipline and a solid motivation to work in a multidisciplinary team;
  • high-level written and oral English communication skills with the ability to represent the research team effectively internally and externally, including presenting research outcomes at national and international conferences;
  • above all, the ambition to be at the forefront of in silico nanostructured materials design.

What can we offer you?        

A 4-years contract with an attractive salary. The selected candidates will moreover get the ability to strengthen their CV within the context of a strongly motivated and multidisciplinary research team and have the ability to contribute to challenging topical research to solve critical societal questions. They will have the opportunity to attend various international conferences and to include research stays in prominent international research teams in this field. Ghent University boasts a strong community that offers a broad range of training and career possibilities for Ph.D. candidates. The training opportunities focus on research and transferrable skills such as time management, presentation, and leadership skills.

How to apply?

We intend to fill this position as soon as possible, preferably in or before September 2025. Complete applications will be considered on receipt, with interviews occurring on a rolling basis until the position is filled. Interested candidates are requested to prepare the following documents:

  1. the filled out application form (see 2025-01_ApplicationForm_FWO_SR.docx underneath);
  2. a one-page cover letter/motivation letter explaining your interest in these positions, how you fit into the propfile, and how you would tackle this research;
  3. a curriculum vitae;
  4. copies of your Bachelor’s and Master's diploma and transcript (certified record of entire enrollment history at educational school), all merged together. Diplomas and transcripts not in Dutch or English should have an official translation in English.

The files should be saved as four separate PDFs and named as follows:

Application_NMRZIFs_PhD_[YourName]_[FileNumber1-4AsListedAbove]

In one mail, these four documents should be sent to Sven.Rogge@UGent.be with the subject “Application FWO NMR-ZIFs YourName”.

Please be aware that only complete applications will be considered.

Lecture Venkat Kapil

On November 17-18, 2024, prof. Venkat Kapil from University College London visited the Center for Molecular Modeling. Aside from the inspiring scientific discussions we had, he also gave a lecture entitled "Machine learning for full quantum simulations: understanding the behaviours of confined and water".

 

AttachmentSize
PDF icon 2024 12 17 - Venkat Kapil.pdf763.18 KB

New publication in Nature Communications: Water motifs in zirconium metal-organic frameworks induced by nanoconfinement and hydrophilic adsorption sites

While nanoconfinement alters the structure and properties of water, it remains unclear what drives these modifications. In our latest compchem Nature Communications work, we disentangle the importance of nanoconfinement and hydrophilic nucleation sites through a series of zirconium-based MOFs. Based on these in silico results, we established an analytical model that allows for complete control over the dimensions of the nanoconfinement and the presence & strength of primary adsorption sites; thereby qualitatively matching the adsorption behaviour found in these MOFs. Furthermore, our model decisively demonstrates the importance of secondary adsorption sites in shaping the water adsorption isotherms by improving the adsorption capacity of the material while maintaining modest desorption energies, as required, for instance, in atmospheric water harvesting.

Read the article here: https://www.nature.com/articles/s41467-024-54358-z

Authors: Aran Lamaire, Jelle Wieme, Sander Vandenhaute, Ruben Goeminne, Sven Rogge, Veronique Van Speybroeck

Lecture Ambarish Kulkarni

On Thursday November 7, 2024, prof. Ambarish Kulkarni from the University of California visited the Center for Molecular Modeling. Aside from the inspiring scientific discussions we had, he also gave a lecture entitled "Accelerated Design of Functional Materials: Overcoming the "Valley of Death" in Heterogeneous Catalysis".

Lecture Hannes Jónsson

On Tuesday October 29, 2024, prof. Hannes Jónsson from the University of Iceland visited the Center for Molecular Modeling. He gave a lecture entitled "Calculations of excited electronic states with density functionals made simple, without introducing time-dependence", after which we had inspiring scientific discussions.

Jelle Wieme receives prestigious De Meulemeester-Piot Prize 2024

Dr. ir. Jelle Wieme has been awarded the Prof. D. De Meulemeester-Piot Prize 2024 that is awarded every four years to a UGent PhD candidate in the field of engineering sciences to encourage scientific research.

In his doctoral thesis under the supervision of prof. dr. ir. Veronique Van Speybroeck, Jelle investigated the phase stability and thermal properties of metal-organic frameworks (MOFs). He performed advanced molecular simulations to better understand these innovative nanomaterials, which are applicable in gas storage and energy management. His work provides valuable insights for the development of MOFs in industrial applications, and emphasizes the need for a balance between porosity and thermal performance. The jury found that Jelle Wieme's thesis on this complex subject was well presented. This award recognizes his contribution to solving societal challenges with sustainable technologies.

Jelle obtained his Master of Science in Engineering Physics in 2015 and his PhD at the Center for Molecular Modelling in 2019. He is currently an advisor at the Centre for Cybersecurity Belgium.

Welcome to our new Master thesis students!

Last Thursday, just before the start of the academic year, we welcomed our new Master thesis students during an introduction session. We wish them an inspiring academic year at Ghent University!

Lecture Gian-Marco Rignanese

On Friday September 13, 2024, prof. Gian-Marco Rignanese from UCLouvain and research director at FNRS visited the Center for Molecular Modeling. Aside from the inspiring scientific discussions we had, he also gave a lecture entitled "Combining the Power of High-Throughput Ab Initio Calculations and Machine Learning towards Materials Informatics".

ERC-funded Ph.D. position on modelling strained interfaces and long-range disorder in functional materials

 

The Rogge group, embedded within the multidisciplinary Center for Molecular Modeling (molmod.ugent.be) at Ghent University, Belgium, is looking for a highly motivated Ph.D. researcher to strengthen our team by performing state-of-the-art computational research in functional materials design. The Ph.D. candidate will investigate how interfaces and long-range disorder in metal-organic frameworks and metal halide perovskites impact their tendency to undergo phase transitions. This requires developing a multistep approach to determine (i) which types of interfaces and long-range disorder are likely to occur in these materials, (ii) how these features can be modelled accurately at currently inaccessible time and length scales, and (iii) how they alter polymorphism in these materials. Answering these questions is vital to understanding how these realistic, finite-sized materials can be adopted in applications.

This position fits within a recent Starting Grant (StG) STRAINSWITCH awarded to prof Sven M. J. Rogge by the European Research Council (ERC). This grant aims to establish strain engineering as a new in silico approach to designing functional nanostructured materials (see, e.g., doi.org/10.1016/j.matt.2023.02.009). We especially welcome candidates with a strong track record who are – or may become – eligible to apply for a prestigious Ph.D. fellowship at our national funding agency or wish to prepare for a European fellowship.

More info about STRAINSWITCH and the different research topics within this ERC StG project

It is often easy to observe the ability of polymorphic materials to undergo a phase transition through changes in colour, conductivity, photovoltaic efficiency, or other functional properties. In contrast, it is challenging to control under which external stimuli, such as stress, temperature, or adsorption, these materials switch. Yet, enabling such polymorphic materials design would be a game changer for pressing societal challenges, from access to drinking water to producing green energy. However, this requires a firm understanding of how changing a material’s structure impacts its polymorphism and macroscopic function.

STRAINSWITCH aims to transform polymorphic material design by establishing the strain engineering concept. The central characteristic of this in silico approach is strain: the extent to which a material deforms due to external or internal triggers. On the one hand, external stimuli generate strain, even before they activate a phase transition. On the other hand, spatial disorder in a structure, tuneable from the atom to the device scale, also induces strain which interferes with external strain fields. Our fundamental idea is that it is possible to systematically predict which disorder is needed to ensure polymorphism only occurs under well-defined external triggers by balancing these internal and external strain fields.

Don't hesitate to contact prof Rogge (Sven.Rogge@UGent.be) for informal inquiries or more information.

More info about the CMM                        

The CMM groups about 40 researchers from the Faculty of Science and the Faculty of Engineering and Architecture at Ghent University with molecular modelling interests. It is unique in the university as it clusters computational researchers with various backgrounds, from multiple departments and faculties. The CMM aims to model molecules, materials & processes at the nanoscale by bringing together physicists, chemists, and (bio-)engineers while stimulating collaborations across disciplines. This multidisciplinary collaborative mission is the DNA of the CMM and is crucial in achieving scientific excellence in molecular modelling.

The CMM focuses on frontier research in six primary areas: computational material research on the nanoscale, model development, spectroscopy, many-particle physics, chemical kinetics in nanoporous materials, and bio-organic & organic chemistry. Our research is performed within a strong network of partners at Ghent University and at an (inter)national level. To pursue excellence, we strongly stimulate interactions between the various researchers in our team and our vast network of national and international partners. The prospective candidates will join a strongly connected research team and collaborate with national and international academic partners. The research of the CMM is internationally regarded to be at the forefront of its field.

Who are we looking for?

We are looking for a highly motivated Ph.D. candidate with: 

  • a Master’s degree or an international equivalent in physical chemistry, chemical physics, condensed matter physics, statistical physics, theoretical physics, or a related field obtained before your first working day at the CMM.
  • demonstrated experience with coding (Python, C, etc.) and quantum chemistry software (Gaussian, VASP, CP2K, etc.) or force-field-based simulations is an advantage;
  • a strong interest in molecular modelling;
  • excellent research and scientific writing skills;
  • perseverance and an independent, proactive working style;
  • the willingness to look beyond the borders of your discipline and a solid motivation to work in a multidisciplinary team;
  • high-level written and oral English communication skills with the ability to represent the research team effectively internally and externally, including presenting research outcomes at national and international conferences;
  • above all, the ambition to be at the forefront of in silico nanostructured materials design.

What can we offer you?        

A 4-years contract with an attractive salary. The selected candidate will moreover get the ability to strengthen their CV within the context of a strongly motivated and multidisciplinary research team and have the ability to contribute to challenging topical research to solve critical societal questions. They will have the opportunity to attend various international conferences and to include research stays in prominent international research teams in this field. Ghent University boasts a strong community that offers a broad range of training and career possibilities for Ph.D. candidates. The training opportunities focus on research and transferable skills such as time management, presentation, and leadership skills.

How to apply?

We intend to fill this position as soon as possible, preferably in or before January 2025. Complete applications will be considered on receipt, with interviews occurring on a rolling basis until the position is filled. Interested candidates are requested to prepare the following documents:

  1. the filled out application form (see 2024-08_ApplicationForm_ERC_SR.docx underneath);
  2. a one-page cover letter/motivation letter explaining your interest in these positions, how you fit into the propfile, and how you would tackle this research;
  3. a curriculum vitae;
  4. copies of your Bachelor’s and Master's diploma and transcript (certified record of entire enrollment history at educational school), all merged together. Diplomas and transcripts not in Dutch or English should have an official translation in English.

The files should be saved as four separate PDFs and named as follows:

Application_STRAINSWITCH_PhD_[YourName]_[FileNumber1-4AsListedAbove]

In one mail, these four documents should be sent to Sven.Rogge@UGent.be with the subject “Application STRAINSWITCH YourName”.

Please be aware that only complete applications will be considered.

AttachmentSize
File 2024-08_ApplicationForm_ERC_SR.docx104.65 KB

Pages

Subscribe to News