Catalysis is of extreme relevance in the production of everyday materials and plays a central role in many aspects of our life.

Promotor: Prof.dr. E.F. Smets, Co-Promotor: L.W. Chatrou

Promotor: Prof.dr. E. Smets, M. Stech

Promotor: Prof.dr. H.P. Spaink, Co-promotor: Dr. B.E. Snaar

In the current global context, there is a pressing need to address sustainable energy supplies to safeguard our Planet and its ecosystems. The choices made by human society have a significant impact on genetic evolution and climate.

Heterogeneous catalysis is essential to many industrial applications. These catalysts are often comprised of supported nanoparticles, which contain various different surface sites.

Promotor: T. Schmidt, Co-Promotor: B.E. Snaar-Jagalska

The aim of the research presented in this thesis was to develop new methods forchallenging systems in liquid-state NMR using paramagnetic effects generated by thetwo-armed probe CLaNP-5.

Op 11 november organiseerde de bacheloropleiding Molecular Science and Technology een corona-proof diploma-uitreiking met een bijzondere afstudeerder: de 18-jarige Ruard van Workum. Al van jongs af aan ontwikkelde Ruard een passie voor scheikunde. Hij begon op 15-jarige leeftijd met de opleiding Molecular…

Mechanical forces are known to play an important role in bacterial colonies. In this dissertation, we study the self-organization at various stages of growing bacterial colonies, and focus on the mechanical effects of cell growth.

Heterogeneous catalysis is one of the fundamental processes of modern life, being common in industrial refinery and hydrogen vehicles, all the way to the living cell. The dissociation of H2 on Cu(111) is an important benchmark system for studying heterogeneous catalysis, with a large and varied amount…

This thesis is about the study of hydrocarbons via infrared spectroscopy.

Large areas of space are filled by molecular clouds that consist of gas and dust grains that are the remnants of dead stars. When these clouds start collapsing, the decreasing temperature and increasing density cause gas particles to start accreting onto dust grain surfaces.

Anionic particles play an important role in biological systems where they fulfil many essential functions for cells.

Promotor: Prof.dr. T. Schmidt, Co-Promotor: S.J.T. van Noort

The long-held desire - to link structure directly to function and to explain molecular mechanisms based on basic chemical or physical principles - is finally coming closer, satisfying not only our scientific curiosity but also offering new solutions to the many challenges in the field of health, energy…

Streptomyces are multicellular, Gram-positive bacteria in the phylum of actinobacteria which produce a high amount of bioactive natural products of which the expression is tightly coordinated with the life cycle.

In surface science there is great effort to move from studying simple, flat model surfaces in vacuum to investigating more complex model catalysts in gas environments (in situ). This thesis gives three examples of such studies using microscopy and spectroscopy.

Metal-organic compounds hold great promise as photoactivated chemotherapy (PACT) agents, leveraging their unique geometric and electronic properties to achieve precise spatiotemporal control over drug activation.

Promotor: F.P. Israel, Co-Promoter: R. Meijerink

This dissertation combines the use of defined microenvironments, high-resolution fluorescence microscopy, and time-resolved analysis, to study intracellular and cellular motility.

Nucleoid associated proteins maintain the architecture of the bacterial chromosome and regulate gene expression, hinting that their role as transcription factors may involve local three-dimensional chromosome re-modelling.

Menselijke cellen beschermen hun eiwitten tegen ontvouwen en samenklonteren. Dat ontdekten biofysicus Alireza Mashaghi en zijn team na zeven jaar diepgaand onderzoek naar de vouwmechanismen van eiwitten. Met een nieuwe, baanbrekende methode slaagde het team erin om een afzonderlijk eiwit te vouwen en…

Microglia support the central and peripheral nervous system by forming the first line of defense against hazardous events. Microglia are increasingly acknowledged as critical players in neurodegenerative diseases, highlighting them as potential therapeutic targets.

This thesis advance our understanding and the application of molecular catalysts relevant to the reduction of oxygen as well as reduction of nitrite.

Heterogeneous catalyzed processes are highly significant to the chemical industry. Dissociative chemisorption (DC) of molecules on surfaces is always considered as a step with a high degree of rate control for heterogeneous catalysis.

The human body consists of hundreds, perhaps thousands of different types of cells, each with different morphologies and functions, despite having the same genome.

Promotor: Jaap Brouwer, Co-promotor: Remus Th. Dame

Promotor: Prof.dr. E. F. van Dishoeck

The increasing resistance of pathogenic bacteria to antibiotics necessitates the discovery of new medicines.

This thesis describes a study from both a theoreticaL and an experimental point of view.

Despite the history of studies on methanol formation from CO2, the dominant elementary reaction steps that constitute the chemical mechanism for this catalyzed process are not determined.

Promotor: H.V.J. Linnartz

Onderzoeksgroepen in het Quantum Matter & Optics onderzoeksprogramma onderzoeken elektronische eigenschappen van interacties van materie en lichtmaterie, met de nadruk op quantuminformatie.

Hybrid zones occur where two species meet and produce offspring (hybrids). Typically, hybrids show a considerable reduction in fitness. In this thesis two hybrid zones are treated.

The formation and evolution of galaxies is fundamentally driven by the formation of new stars out of cold gas.

Michel Orrit heeft een subsidie ontvangen uit het NWO-TTW Open Technologieprogramma. Hij gaat de kleine half miljoen euro gebruiken om individuele moleculen in beeld te brengen zonder fluorescentie te gebruiken.

Promotor: Prof.dr. E. Bouwman, Co-Promotor: S. Bonnet

Developing new medicines is one of modern science's most significant hurdles, a process marked by high costs, long timelines, and frequent failures of promising candidates.

Several techniques are explored for going beyond the born-oppenheimer static surface model for molecule-surface reactions.

The work in this thesis demonstrates how to obtain an atomic-scale picture of a diverse set of complex surface structures observed using STM, under disparate conditions.

Het is nog nooit gelukt om een enkel elektron te detecteren met zichtbaar licht via slechts één molecuul. Leids natuurkundige Michel Orrit en zijn onderzoeksgroep hebben nu een molecuul geïdentificeerd dat gevoelig genoeg is om een elektron te detecteren op een afstand van honderden nanometers. De resultaten…

Eiwitten in cellen visualiseren zonder invasieve technieken? Dat kan met behulp van fluorescentie. Michel Orrit, winnaar van de Spinozapremie 2017 én grondlegger van het vakgebied single molecule optics, legde op 18 januari aan de leden van het Natuurwetenschappelijk Gezelschap Leiden en andere geïnteresseerden…

Op 12 september heeft Michel Orrit zijn Spinozaprijs in ontvangst genomen uit handen van OCW staatssecretaris Sander Dekker in de Koninklijke Schouwburg in Den Haag. Met de prijs is een premie gemoeid van 2,5 miljoen euro, die vrij is te besteden aan wetenschappelijk onderzoek naar keuze, en het felbegeerde…

Promotor: T. Schmidt

In the first part of this thesis we study the geometry of folding patterns.

The Copenhagen interpretation of quantum mechanics states that a measurement collapses a wavefunction onto an eigenstate of the corresponding measurement operator.

This thesis presents pioneering work on the panchromatic emission of some of the most luminous galaxies in the early Universe: star forming galaxies and active galactic nuclei.

Animal diet studies are critical for understanding ecological processes such as trophic interactions, energy flow, and nutrient cycling. By examining what animals consume, ecologists gain insights into species specialization, predator-prey relationships, and ecosystem management.