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AbstractIn this work, I aimed to accurately simulate the Raman optical activity (ROA) signatures of flexible solute molecules in their environment. Indeed, these systems are quite challenging due to the potentially huge number of conformers—that is, local minima on the potential energy surface (PES). Furthermore, the environment can drastically alter the PES, as evidenced by experimental ROA spectra that vary significantly depending on the molecule’s conformation and its surroundings. To address this issue, we have developed a hierarchy of methodologies designated M1, M2, and M3. In M1 and M2, the so-called static approach is used: one or more conformers are identified, their geometries are reoptimized at the Density Functional Theory (DFT) level, and their vibrational signatures are simulated, typically using the harmonic approximation. The initial list of conformers was obtained using the CREST algorithm. In M1, the solvent is treated implicitly, whereas in M2, explicit solvent molecules are added around the solute molecule. In M3, we perform ab initio molecular dynamics simulations of the solute molecule surrounded by explicit solvent molecules. The spectrum is obtained by evaluating time-correlation functions along the trajectory. Our first systems of interest were cryptophane derivatives. These are flexible cage-like systems consisting of two hemispheres connected by three -O-(CH₂)n-O- (denoted Cr–nnn) linkers that exhibit chiroptical properties. For Cr–111, the smallest possible cryptophane, the M1 methodology showed good agreement with experimental data, especially in the fingerprint region. However, we demonstrated that the relative ratio between the different conformers was strongly influenced by the choice of the exchange-correlation (XC) functional in our DFT calculations, highlighting the sensitivity of the potential energy surface (PES) description. Cr–222 molecules have been shown to be more flexible, as evidenced by a greater number of significant conformers. The overall agreement with experimental data was also satisfactory. Finally, to test our different approaches (M1–M3), I performed new ROA measurements of amino acids in water at the University of Bordeaux in Dr. Daugey’s laboratory. When compared to our simulations, we clearly observed an improvement in the ROA signatures when explicit water molecules were added to our simulations (M2 vs. M1). Unfortunately, the M3 method did not perform as expected, and further investigation is needed. Overall, I have shown that the PES, as described by our various methodologies, is highly sensitive to various simulation parameters—such as the XC functional, the number and position of explicit solvent molecules, and so on—and that all of these factors strongly influence the simulated ROA signatures.JuryProf. Francesca CECCHET (UNamur), ChairProf. Vincent LIÉGEOIS (UNamur), SecretaryProf. Benoît CHAMPAGNE (UNamur)Prof. Carine CLAVAGUÉRA (University of Paris-Saclay)Dr. Nicolas DAUGEY (University of Bordeaux)

AbstractEnvironmental change rarely occurs as a single, isolated event; organisms and communities typically experience one stressor against the backdrop of another that has already passed. Arunima Sikder’s doctoral thesis examines whether an organism’s past environment shapes its response to the environment that follows, and whether that influence propagates upward to affect the stability of the communities to which these organisms belong.The thesis addresses this question in Synechococcus sp., a globally significant marine primary producer, using thermal and chemical stressors as its two environmental drivers. Working across three levels of biological organization, the study examines how past environments shape responses to subsequent ones—whether they occur in sequence, fluctuate, or occur in combination—using functional traits as the common metric for measuring these responses.The results reveal three key findings. First, sensitivity to a stressor depends on the sequence of exposure, not on the stressor alone. Second, response diversity predicts community stability only when measured under the community’s actual acclimation history, rather than under sustained conditions as conventional wisdom assumes. Third, an apparent contradiction in biodiversity–ecosystem function theory—a negative relationship between functional diversity and performance.Together, these findings suggest that sensitivity, response diversity, and functional diversity should be treated as state-dependent quantities rather than fixed properties, with implications for how the performance of biological systems is measured and modeled under increasingly variable environmental conditions.JuryProf. Alice DENNIS (UNamur), ChairProf. Frederik DE LAENDER (UNamur), SecretaryProf. Maren STRIEBEL (Carl von Ossietzky University Oldenburg)Prof. Giulia GHEDINI (Monash University)Prof. Eli THORÉ (UNamur)

What's on the agenda for everyone 9:00 a.m. | Welcome reception at the Pedro Arrupe, Rue de Bruxelles 67, 5000 Namur9:30 a.m. | Ceremony at the Espace Pedro Arrupe 11:00 a.m. | Back-to-School Celebration at Saint-Loup Church—to be confirmed, Rue du Collège, 5000 Namur—followed by a welcome for students by the student clubs.Other specific activities for this day are available on each faculty’s webpage. More information on the Back-to-School page

Take part in our open morning Given the works in the rue de Bruxelles and the renovation of part of the University parking lots, we invite you to use public transport whenever possible (train or bus) to reach Namur. UNamur boasts an ideal location, in the heart of the city just a five-minute walk from the TEC and SNCB train stations.If you're coming by car, take a look at the parking map provided. Look forward to seeing you on Saturday, June 29!

Stanford University has published a prestigious ranking that highlights the most influential researchers in a wide range of scientific fields. The list, based on bibliographic criteria, aims to provide a standardized means of identifying the world's scientific leaders. It is one criterion among others for assessing the quality of scientific research. Twelve researchers from the University of Namur are among them!

Animated by a desire to help the most disadvantaged, Father Pedro Opeka, a Lazarist priest, devotes his life to improving the living conditions of Madagascar's marginalized populations. His strong humanitarian commitment has resulted in the creation of Akamasoa, an association that provides shelter, education and healthcare to thousands of Malagasy people. By transforming the lives of an entire community in this way, he has become a symbol of hope in a country beset by poverty.

A delegation from the Université de Namur took part in an exploratory mission to the Université Cheikh Anta Diop (UCAD) in Dakar, Senegal. The aim: to discover the research carried out in the field, meet UCAD researchers and initiate future collaborations between the two institutions.

The University of Namur is soon to offer two inaugural lessons for two Francqui Chairs, one in the Faculty of Science and the other in the Faculty of Law. Open to all, the inaugural lectures will be followed by a local drink. These events are free, upon registration.

To mark International Women's Day, celebrated on March 8, we invite you to discover the portraits of seven inspiring women from the university's seven faculties. Throughout March, a series of portraits of women from the university will be on display in various areas of the campus. Conceived and produced by four UNamur students and coordinated by the University Community Life Service (VéCU), this project offers an inspiring showcase for the careers, voices, and commitments of these women who bring the institution to life on a daily basis.  

Save the date! On Saturday June 28, 2025, from 1pm to 5pm, UNamur once again opens its doors to you before the summer vacations.At the programProfessors, assistants, students and staff members look forward to welcoming you to answer all your questions about your future studies;share with you their experience of university life and its many opportunities for fulfillment;guide you through your final practical steps: registration, preparatory courses, finding accommodation, financial aid and more.Forthcoming informationThe afternoon's detailed program will be available some ten days before the event. Find out more about the open house

Something for everyone 09:30 | Welcome ceremony for new students11:00 | Back-to-school celebration at Saint-Aubain Cathedral (Place Saint-Aubain - 5000 Namur), followed by student welcome by the Cercles. Read more