Intézeti szeminárium
Intézeti szeminárium
2025/26 őszi szemeszter (autumn semester)
18 September (Thursday) 15:00, Bruckner auditory (063)
Tokyo Metropolitan University, Japan
Advanced Fe-and Sn-Mössbauer Studies of Na-Ion Battery Electrodes and Photocatalysts for Environmental Purification
The purification of wastewater and the utilization of renewable energy are critical environmental challenges facing humanity. In this seminar, the presenter will introduce two recent developments: electrically conductive tin-containing vanadate glass as cathode active materials for sodium-ion batteries, and iron oxide nanoparticles that exhibit visible-light-activated photocatalytic activity for environmental remediation. Both materials have been characterized using radioanalytical techniques, including Mössbauer spectroscopy and X-ray Absorption Fine Structure (XAFS).
25 September (Thursday) 15:00, Bruckner auditory (063)
Department of Chemistry, University of California, Berkeley, USA
Perturbation theory for electron correlation made better and faster?
Rayleigh-Schrodinger perturbation theory, and its ab initio application to manyelectron systems via Moller-Plesset (MP) perturbation theory, is not regular order by order, and therefore can exhibit erratic behavior for systems with small HOMOLUMO gaps, and even for intermolecular interaction energies of large molecules. With this in mind, in the first part of this talk, I will discuss a new approach to regularize MP2 theory against divergence in the small gap limit. The idea is to modify Brillouin-Wigner perturbation theory to be size-consistent as well as regular at second order to define BW-s2. This can also be viewed as a form of RayleighSchrodinger perturbation theory with a non-Moller-Plesset partitioning, which appears to offer considerable promise.
My second topic is revisiting the design of local correlation methods at the doubles level, for MP2 and BW-s2, as well as higher-level methods. The main challenge for local correlation is to achieve full control over errors such that a user only needs to select a single numerical drop tolerance. To achieve this goal, we have designed a new “single threshold” approach to local correlation that also avoids the use of projected AOs and PNOs to span the virtual space by instead employing a localized orthogonal virtual basis. Accuracy and performance will be assessed via a range of example calculations. Kapuy’s double perturbation theory plays a significant role in this approach, as it does in many local correlation models. We will show that our latest implementation of this single-threshold numerical sparsity approach provides significantly higher numerical accuracy and/or significantly lower compute cost than the domain-localized pair natural orbital scheme, as implemented in ORCA.
16 October (Thursday) 15:00, Bruckner auditory (063)
Department of Experimental Physics, Institute of Physics and Technology, Ural Federal University, Ekaterinburg, Russian Federaition
Application of 57Fe Mössbauer Spectroscopy: Iron-Containing Pharmaceuticals and Iron-Bearing Phases in Meteorites
Mössbauer spectroscopy, based on the nuclear g-resonance phenomenon named the Mössbauer effect, is the most powerful technique for studying the hyperfine interactions of so-called Mössbauer isotopes/nuclei (e.g., 57Fe, 119mSn, 121Sb, 125Te, 127I, 197Au, 151Eu, etc.). The Mössbauer hyperfine parameters are related to the electron and magnetic structures, valence and spin state of these isotopes, dynamics of the Mössbauer nuclei, symmetry of crystal structure around the Mössbauer nuclei and its local microenvironments, etc. Therefore, Mössbauer spectroscopy, since the observation of the Mössbauer effect in 1958 became a widely used spectroscopic tool from chemistry and physics to biophysics and biomedicine. 57Fe is the most acceptable Mössbauer isotope. Therefore, all iron-containing materials in the solid state, from crystalline to amorphous, can be studied by Mössbauer spectroscopy. Some applications of Mössbauer spectroscopy will be demonstrated in the examples of studies on the iron-containing pharmaceuticals and iron-bearing phases in meteorites.
Most iron-containing pharmaceuticals (medicaments and dietary supplements) are used for the treatment or prevention of iron deficiency anemia. These pharmaceuticals contain iron in various compounds, e.g., ferrous fumarate (FeC4H2O4), ferrous sulfate (FeSO4), ferrous gluconate (C12H24FeO14), ferrous bisglycinate chelate (C4H8FeN2O4), ferric pyrophosphate (Fe₄(P₂O₇)₃), various iron polysaccharide complexes with nanosized ferric hydrous oxide cores (e.g., akaganéite b-FeOOH, ferrihydrite 5Fe2O3 × 9H2O) which are ferritin analogues, etc. The study of various pharmaceuticals by Mössbauer spectroscopy (see, e.g., [1–3]) demonstrated that some pharmaceuticals contain ferric compounds in addition to ferrous ones, in some cases there are several ferrous components instead of one, as well as in the case of pharmaceuticals containing ferrous bisglycinate chelate there were no consistency between different products due to different variety of spectral components related to different iron states.
Meteorites are space messengers which carry information about the Solar System formation and evolution. Meteorites are divided into iron, stony-iron and stony meteorites on the basis of their phase (mineral) and chemical compositions. The main iron-bearing minerals and phases in meteorites are: olivine (Fe, Mg)2SiO4, orthopyroxene (Fe, Mg)SiO3, clinopyroxene (Fe, Ca, Mg)SiO3, troilite FeS, Fe-Ni-Co alloys with a-Fe(Ni, Co), a2-Fe(Ni, Co), g-Fe(Ni, Co) and g-FeNi phases, chromite FeCr2O4, hercynite FeAl2O4, ilmenite FeTiO3, schreibersite (Fe, Ni)3P and its microcrystals named rhabdites, daubréelite FeCr2S4, etc. Several examples of the study of ordinary chondrites (stony), pallasites (stony-iron) and iron meteorites by Mössbauer spectroscopy (see, e.g., [4–9]) demonstrate the possibility of the technique to reveal various iron-bearing phases. At the same time, the Mössbauer parameters can be used for meteorites' detailed analyses.
[1] Alenkina I.V., Kovacs Kis V., Felner I., Kuzmann E., Klencsár Z., Oshtrakh M.I. Structural and magnetic study of the iron cores in iron(III)-polymaltose pharmaceutical ferritin analogue Ferrifol®. J. Inorg. Biochem., 2020, 213, 1112020.
[2] Alenkina I.V., Chukin A.V., Leitus G., Denisova O.V., Gracheva M., Felner I., Kuzmann E., Homonnay Z., Oshtrakh M.I. Analysis of the iron states in iron-containing pharmaceutical products using Mössbauer spectroscopy. J. Pharm. Biomed. Anal., 2024, 237, 115745.
[3] Alenkina I.V., Oshtrakh M.I. Control of the iron state in pharmaceuticals used for treatment and prevention of iron deficiency using Mössbauer spectroscopy. J. Pharm. Sci., 2024, 113, 1426–1454.
[4] Maksimova A.A., Oshtrakh M.I. Applications of Mössbauer spectroscopy in meteoritical and planetary science, Part I: undifferentiated meteorites. Minerals, 2021, 11, 612.
[5] Maksimova A.A., Goryunov M.V., Oshtrakh M.I. Applications of Mössbauer spectroscopy in meteoritical and planetary science, Part II: differentiated meteorites, Moon and Mars. Minerals, 2021, 11, 614.
[6] Goryunov M.V., Maksimova A.A., Oshtrakh M.I. Advances in analysis of the Fe-Ni-Co alloy and iron-bearing minerals in meteorites by Mössbauer spectroscopy with a high velocity resolution. Minerals, 2023, 13, 1126.
[7] Goryunov M.V., Varga G., Dankházi Z., Chukin A.V., Felner I., Kuzmann E., Homonnay Z., Muftakhetdinova R.F., Grokhovsky V.I., Oshtrakh M.I. Characterization of iron meteorites by scanning electron microscopy, X-ray diffraction, magnetization measurements and Mössbauer spectroscopy: Kayakent IIIAB. Meteorit. & Planet. Sci., 2025, 60, 1421–1432.
[8] Goryunov M.V., Petrova E.V., Chukin A.V., Maksimova A.A., Varga G., Dankházi Z., Felner I., Leitus G., Gritsevich M., Kuzmann E., Homonnay Z., Kohout T., Oshtrakh M.I. Comparison of the iron-bearing crystals and phases from Tamdakht H5 and Annama H5 ordinary chondrites by X-ray diffraction, magnetization measurements and Mössbauer spectroscopy. Meteorit. & Planet. Sci., 2025, 60, 1520–1544.
[9] Goryunov M.V., Felner I., Varga G., Dankházi Z., Chukin A.V., Naumov S.P., Leitus G., Muftakhetdinova R.F., Kuzmann E., Homonnay Z., Oshtrakh M.I. Magnetic features of some extraterrestrial Fe-Ni-Co alloys: study using magnetization measurements and Mössbauer spectroscopy. Phys. B: Cond. Mat., 2025, 716, 417656.
13 November (Thursday) 15:00, Bruckner auditory (063)
Laboratoire de Chimie et Physique Quantiques, CNRS - Université Toulouse III-Paul Sabatier, France
Nuclear size effects in rovibrational spectra: A tale with a twist
In the early 1980s Tiemann and co-workers [1] conducted a series of high-resolution rotation spectroscopy experiments for isovalent, closed-shell diatomics AB, which aimed at an accurate assessment of spectroscopic constants as for example, the equilibrium bond length Re or the rotational constant Be. In the particular case of thallium and lead compounds, they were not able to bring their measured isotope data in agreement using the existing theory of adiabatic and non-adiabatic correction terms to the Born–Oppenheimer (‘‘clamped nuclei’’) approximation, leading them to propose that the discrepancy was due to the effect of a finite nuclear volume.
We provide a new derivation for the electron–nucleus electrostatic interaction energy, which is basically independent of the choice of model for the nuclear charge distribution. Starting from this expression, we derive expressions for the electronic, rotational and vibrational field shift parameters in terms of effective electron density and its first and second derivatives with respect to internuclear distance. [3,4]
The derivation is a nice exercise in the use of variational perturbation theory.
We also discuss the implications of this on geochemistry.
[1] E. Tiemann, H. Arnst, W. Stieda, T. Törring, J. Hoeft, Chem. Phys. 67 (1982) 133
[2] H. Knöckel, E. Tiemann, Chem. Phys. 68 (1982) 13
[3] Stefan Knecht and Trond Saue, Chem. Phys. 401 (2012) 10
[4] Adel Almoukhalalati, Avijit Shee and Trond Saue, PCCP 18 (2016) 15406
20 November (Thursday) 15:00, Bruckner auditory (063)
Institute of Organic Chemistry, Faculty of Pharmacy, Semmelweis University, Budapest, Hungary;
HUN-REN Artificial Transporter Research Group, Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Budapest, Hungary
Sustainable Flow Chemistry for Peptide Synthesis and Drug Discovery
The synthesis of peptides remains a cornerstone of modern drug discovery and peptide-based therapeutics. Since Merrifield's pioneering work, solid-phase peptide synthesis (SPPS) has evolved substantially, yet traditional methods still rely on large excesses of amino acids and typically employ environmentally hazardous solvents such as DMF. In response to these limitations, we have developed a sustainable and scalable approach that integrates continuous-flow (CF) technology with the use of propylene carbonate (PC)—a biodegradable, low-toxicity solvent recognized among the greenest alternatives available. [1]
By optimizing reaction parameters within a continuous-flow setup, we successfully reduced amino acid equivalents to as low as 1.5 equivalents, while maintaining excellent coupling efficiencies for all 20 proteinogenic amino acids. [2] Notably, propylene carbonate effectively replaced DMF in SPPS without requiring additional optimization, demonstrating its direct compatibility and highlighting its potential as a broadly applicable green solvent.
Our method was further validated by the efficient scale-up of complex peptide syntheses, including β-peptide foldamers with alicyclic side chains and N-methylated peptides, all obtained in high yields and purities. Even challenging or cost-intensive sequences were synthesized with minimal reagent waste and reduced solvent consumption. These findings underscore the feasibility of merging green chemistry principles with industrial-scale peptide production, offering a more sustainable and economically viable route for both routine and specialized peptide synthesis. [3]
The technology was utilized for some peptide-based drug discovery projects.
[1] Orsy, G.; Fülöp, F.; Mándity, I. M. Green Chem 2019, 21, 956.
[2] Mándity, I. M.; Ötvös, S. B.; Fülöp, F. ChemSusChem 2014, 7, 3172.
[3] Varró, N.; Erdei, E.; Mándityné Huszka, B.; Mándoki, A.; Mándity, I. M. Chemistry‐Methods, 2025, 2500010
4 December (Thursday) 15:00, Bruckner auditory (063)
Servier Research Institute of Medicinal Chemistry, Budapest, Hungary
The targeted degradation of proteins: A new approach in medicinal chemistry
The inhibition or activation of enzymes has long been acknowledged as a useful therapeutic approach, and the majority of today’s drugs act this way. There is increasing evidence however, that the activity of some of these drugs is achieved through decreasing or increasing the amount of a given protein in the cell. This observation and our better understanding of the cellular protein degradation machinery opened the door to a new class of drugs, the degraders. The lecture will provide an overview of this blooming area through some of our own examples.
2024/2025 tavaszi szemeszter (spring semester)
13 February (Thursday) 15:00, Gróh auditory (062)
I. Physikalisches Institut, Universität zu Köln, Germany
Investigating molecular ions with leak-out-spectroscopy
Leak-out-spectroscopy (LOS) is a rather novel ion-trap-based action spectroscopy method. LOS exploits the fact that vibrational energy of a laser-excited ion can be converted into kinetic energy in a collision with a suitable neutral molecule or atom. The ions are thus accelerated and may leave the trap towards a detector. By counting the "leaked-out" ions as a function of the laser wavelength, a spectrum is generated. The invention of LOS has boosted the spectroscopy of molecular ions, as it is a universal and very sensitive technique.
In this presentation, I will focus on the application of LOS to astrophysically relevant cations, in particular on exotic ions consisting of only helium and hydrogen. Such systems are also interesting because they are few-particle-systems and therefore serve as a testing ground for high-level theoretical approaches!
27 February (Thursday) 15:00, Gróh auditory (062)
Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
Papain-like peptidases – allostery, oligomerization and protein engineering
Papain-like cysteine peptidases, called cysteine cathepsins in animals, are predominantly monomeric, single-domain endopeptidases with a broad substrate specificity. In recent decades, several human cathepsins have been associated with various diseases, and their inhibition has been explored as a potential treatment, albeit with limited success. These seemingly simple enzymes have been shown to have sophisticated regulatory mechanisms. We have shown that some, e.g. cathepsin K, can be allosterically regulated by polyanionic polymers such as glycosaminoglycans as well as by small molecule effectors, and molecular dynamics simulations have shown that effectors stabilise pre-existing conformations of the active site. We have also extended our work to cathepsin C, which is an exception in the family as it is a homotetramer and not a monomer. It showed similar susceptibility to small molecule effectors as the monomeric enzymes, but otherwise no additional behaviour that depends on its oligomeric state, such as cooperativity. Interestingly, a recombinant monomeric variant of the enzyme had nearly identical functional properties to the tetramer. Based on these results and the biotechnological potential of these enzymes, we are continuing our research to improve them through protein engineering. Our goal is to produce oligomeric variants with improved functional properties, such as cooperativity. To this end, we have also developed a novel system for the detection of protein homodimerization in Escherichia coli, which is currently being tested for use in protein engineering and drug discovery.
6 March (Thursday) 15:00, Gróh auditory (062)
Institute of Chemistry, Faculty of Science, Pavol Jozef Šafárik University in Košice, Slovakia
Development of green analytical procedures
The aim of this presentation is to summarize the developments in the field of green analytical chemistry at the Department of Analytical Chemistry of the P.J. Safarik University in Kosice. We will focus on the following questions: Green chemistry principles vs Green analytical chemistry (GAC) principles; How to satisfy the GAC? Important components of analytical procedures in the aspect of GAC. Practical consequences of GAC principles for selected parameters of analytical process. Milestones in GAC. Application of the liquid drop in analytical chemistry. Sample pre-treatment. Conventional liquid–liquid extraction (LLE) vs liquid-phase microextraction (LPME). Main categories of LPME, advantages and limitations. Dispersive liquid-liquid microextraction (DLLME), evolution, factors affecting DLLME/DLPME, advantages, disadvantages, problems, limitations of the technique. Various modes of DLLME. DLLME vs DLPME. Acronyms. Automation. Coupling of DLLME to detection techniques. Single drop microextraction (SDME). Application of the optical probe in analytical chemistry. Application of green solvents (deep eutectic solvents). Green metrics.
20 March (Thursday) 15:00, Gróh auditory (062)
Fachdidaktikzentrum Chemie, Univestität Graz, Austria
Communicating, Experiencing and Understanding Chemistry – Science Communication Between Outreach and Education
Science communication takes many forms—from public events to social media—but how effective are these approaches in reaching and educating school students? While universities are highly active in public engagement, do these efforts truly reach young audiences? What role do social media play, and where does real learning happen? I will discuss insights from our projects and their impact, focusing on the Chemical Christmas Lecture and social media outreach. Using the GlacierXperience project as an example, I will also highlight how out-of-school learning can be designed to engage students with current scientific topics, provide information, and give a glimpse into actual scientific research.
This talk invites a discussion on how we can bridge the gap between outreach and education—ensuring that science communication not only inspires but also fosters deeper understanding.
3 April (Thursday) 15:00, Gróh auditory (062)
Circular Chemicals at MOL Group, Hungary
The Future of Plastics: Circular Solutions and Regulatory Challenges in the EU
This presentation aims to provide a comprehensive understanding of the challenges and opportunities within the polymer industry's transition to a circular economy, highlighting MOL Group's strategic responses to regulatory pressures and market dynamics.
The polymer industry is undergoing a major shift towards sustainability, driven by stringent EU regulations and circular economy principles. This presentation explores the company’s strategic initiatives in recycled plastics and their alignment with evolving EU policies.
An overview of MOL Group’s operations is provided, highlighting circular practices within its downstream and polymer value chains. A key focus will be the EU’s regulatory landscape, particularly the Packaging and Packaging Waste Regulation (PPWR), and its impact on the plastics industry—shaping market dynamics, capacity developments, and feedstock availability.
Current recycling rates are assessed, waste generation, and industry progress toward EU targets, identifying gaps in brand owners' commitments. The session will also showcase MOL Group’s mechanical recycling operations—Aurora Kunststoffe and ReMat Zrt.—and its chemical recycling collaboration with Lummus Technology in Hungary.
This presentation provides insights into the challenges and opportunities of transitioning to a circular polymer economy, demonstrating how MOL Group is responding to regulatory and market shifts.
24 April (Thursday) 15:00, Gróh auditory (062)
Institute of Biochemistry, ETH Zürich, Switzerland
From SARS-CoV-2 membrane proteins to protein-RNA phase separation – how can we use multi-faceted bioNMR spectroscopy as a Swiss knife?
BioNMR spectroscopy is a powerful and versatile tool for exploring the structure, dynamics, and interactions of biomolecules. In this talk, I will illustrate its broad applications through recent studies on viral membrane proteins and biomolecular phase separation.
First, I will present solid-state NMR investigations of SARS-CoV-2 accessory membrane proteins, highlighting their structural features, oligomerization, and potential interactions with host proteins. These findings provide insights into their roles in viral pathogenicity.
Second, I will discuss how solution-state NMR reveals the molecular mechanisms underlying protein-RNA liquid-liquid phase separation, a key process in formation of biocondensates in cells. By examining the phase separation behavior hnRNPC1 protein and its interactions with RNA, we aim to obtain a deeper understanding of ribonucleoprotein particle assembly and function.
These examples showcase how advanced NMR techniques can address fundamental questions in structural biology and biophysics, offering a molecular-level perspective on complex biochemical phenomena.
8/9 May (Thursday, Friday) - TBD
Chemistry – Quantum Theory Project, University of Florida, USA
TBA – Honorary Professorship Lecture on Pázmány or Eötvös Day
22/23 May (Thursday, Friday)
TBA – Science and Report Day Lecture(s)
29 May (Thursday) 15:00, Gróh auditory (062)
Department of Chemistry, The George Washington University, Washington, USA
Metabolomics of Single Cells in their Natural Environment
In multicellular organisms, cells assemble into tissues with specific functions. Tissue embedded cells operate a selection of metabolic pathways for the synthesis and degradation of a collection of small molecules that serve growth, signaling, and reproduction. Capturing the spatiotemporal distributions of metabolites, including lipids, with cellular granularity gives new insight into the functioning of tissues. We have developed ambient ionization techniques for mass spectrometry (MS) that can report on the metabolite content of functioning cells with high throughput and targeting capabilities. Image analysis and morphometry of brightfield and fluorescence microscope images are used to target selected cell types, followed by mid-IR laser ablation of individual cells. The ablation plume is ionized by an electrospray (laser ablation electrospray ionization, LAESI). Ion mobility separation (IMS) of the produced ions is followed by time-of-flight or Fourier transform ion cyclotron resonance MS for the determination of cellular metabolite abundances. Cell-type specific small molecule compositions are determined and correlated with active metabolic pathways characteristic to cellular functions. Metabolite abundance distributions reflect population heterogeneity through metabolic noise levels and reveal hidden cellular phenotypes segregated into subpopulations functioning in specific metabolic states. Examples of spatial metabolomics are presented for various cell types including human hepatocytes, Arabidopsis thaliana and onion epidermal cells, and root nodule cells of soybean in nitrogen fixing symbiosis with rhizobia.
2024/25 őszi szemeszter (autumn semester)
October 2. (Wednesday) 15:00, Ortvay auditory (0.81)
Lehrstuhl für Organische Chemie II, Ruhr-University Bochum, Germany
Preparation and Spectroscopic Characterization of Interstellar Relevant Imine Species
Simple imines are frequently used as building blocks in the synthesis of more complex molecules. In solution imines are typically prepared from carbonyl compounds and ammonia or primary amines, respectively. The simplest aldimine, formaldimine (H2CNH), has been discovered in space but cannot be isolated on Earth due to polymerization or oligomerization when concentrated. Aldimine building blocks play a key role in the formation of biorelevant molecules like amino acids or nucleobases in prebiotic chemistry. However, spectroscopic data of the compound class are rare or missing at all due to their high reactivity and the absence of molecular precursors for an on-demand mild generation. The overall goal of this project is to learn more about interstellar and prebiotic imine chemistry and characterize often proposed but yet elusive imine species.
1,2-Diiminoethane was photochemically prepared from explosive 1,2-diazidoethane in solid argon at 3 K and characterized by infrared and UV/Vis spectroscopy. In aqueous solution the simplest diimine serves as a fundamental building block for imidazole heterocycles.
The simplest α-imino acid, namely glycine imine, was prepared by UV irradiation of azidoacetic acid in solid argon at 3 K and characterized by IR and UV/Vis spectroscopy. In aqueous solution at higher concentrations glycine imine undergoes self-reduction to glycine by oxidative decarboxylation chemistry. The imine serves a critical intermediate in prebiotic amino acid synthesis.
2-Iminoacetaldehyde was proposed as an interstellar molecule and prepared by photolysis of 2-azidoacetaldehyde in solid argon at 3 K and low density amorphous water ice. The imine was characterized by characterized by infrared and UV/Vis spectroscopy.
References
[1] A. K. Eckhardt Chem. Commun. 58, 8484–8487 (2022).
[2] V. Paczelt, R. C. Wende, P. R. Schreiner and A. K. Eckhardt Angew. Chem Int. Ed. 62, e202218548 (2023).
[3] V. D. Drabkin, V. Paczelt and A. K. Eckhardt Chem. Commun. 59, 12715–12718 (2023).
October 16. (Wednesday) 15:00, Ortvay auditory (0.81)
Univ. Prof. Dr. Hinrich Grothe
TU Wien, Institute of Materials Chemistry, Getreidemarkt 9/BC, 1060 Vienna, Austria
The efficiency of ice-nucleating macromolecules from Betula pendula pollen
Various aerosols, including mineral dust, soot, and biological particles, can act as ice nuclei, initiating the freezing of supercooled cloud droplets. Cloud droplet freezing significantly impacts cloud properties and, consequently, weather and climate. Some biological ice nuclei exhibit exceptionally high nucleation temperatures close to 0 °C. Ice Nucleating Macromolecules (INMs) found on pollen are typically not considered among the most active ice nuclei. Still, they can be highly abundant, especially for species such as Betula pendula, a widespread birch tree species in the boreal forest. Recent studies have shown that certain tree-derived INMs exhibit ice nucleation activity above ‒10 °C, suggesting they could play a more significant role in atmospheric processes than previously understood. Our study reveals three distinct INM classes active at ‒8.7 °C, ‒15.7 °C, and ‒17.4 °C are present in Betula pendula. Freeze-drying and freeze-thaw cycles noticeably alter their ice nucleation capability, and the results of heat treatment, size, and chemical analysis indicate that INM classes correspond to size-varying aggregates, with larger aggregates nucleating ice at higher temperatures in agreement with previous studies on fungal and bacterial ice nucleators. Our findings suggest that Betula pendula INMs are potentially important for atmospheric ice nucleation because of their high prevalence and nucleation temperatures.
November 14. (Thursday) 15:00, Bruckner auditory (063)
Cardiff University, UK
How far can we go with single-configuration quantum chemistry?
Traditional quantum chemistry begins with the mean field model, where the orbital approximation leads to a single Slater determinant. Electron correlation effects are then introduced perturbationally, or through coupled-cluster theory, or modelled with a density functional. When correlation is strong, multiconfigurational reference methods offer a general flexible approach that avoids the qualitative failure of the Hartree-Fock reference, but they have the disadvantages of strong cost scaling with system size, and, in most cases, a lack of size extensivity. In this lecture I will explore the extent to which the useful domain of single-reference methods can be extended. The consideration will include alternative coupled-cluster formulations, new forms of perturbation theory, and extension to the correlation of electrons with vibrations (beyond Born-Oppenheimer) and photons (molecules in an optical cavity).
November 20. (Wednesday) 15:00, Ortvay auditory (0.81)
Department of Physics and Astronomy, University College London, London, UK
Enhanced Sampling Simulations of Biomolecular Systems
Phosphate catalytic enzymes are essential and ubiquitous to all forms of life. While structures of these proteins are typically readily available, prediction and design of their function and activity is a key current challenge. Here we present computing intensive free energy calculation data and machine learning applications to predict catalytic activity for prototype examples including Ras [1]. Our work highlights the important role of coupled proton transfer steps in the catalytic mechanism using the finite-temperature string method. This allows us to use multiple collective variables that govern the reaction path. Identification of these collective variables in complex processes presents a major problem. We offer promising AI-driven algorithms to help identify essential reaction coordinates in biomolecular processes [2,3].
References
[1] Berta, D.; Gehrke, S.; Nyíri, K.; Vértessy, B. G.; Rosta, E. Mechanism-Based Redesign of GAP to Activate Oncogenic Ras. JACS, 2023, 10.1021/jacs.3c04330.
[2] Badaoui, M.; Buigues, P. J.; Berta, D.; Mandana, G. M.; Gu, H.; Földes, T.; Dickson, C. J.; Hornak, V.; Kato, M.; Molteni, C.; Parsons, S.; Rosta, E. Combined Free-Energy Calculation and Machine Learning Methods for Understanding Ligand Unbinding Kinetics. J. Chem. Theory Comput. 2022, 10.1021/acs.jctc.1c00924.
[3] Buigues, PJ; Gehrke, S; Badaoui, M; Mandana, G. M.; Qi, T; Bottegoni, G; Rosta, E. Investigating the Unbinding of Muscarinic Antagonists from the Muscarinic 3 Receptor. bioRxiv; 2023, 10.1101/2023.01.03.522558.
December 4. (Szerda) 15:00, Ortvay terem (0.81)
Kiss László, Széchenyi- és Prima Primissima-díjas csillagász
HUN-REN Csillagászati és Földtudományi Központ
Horgosról a csillagokig és tovább ‒ egy csillagász kalandozásai a nagyvilágban
Előadásomban bemutatom, hogyan válhat egy horgosi kisdiákból nemzetközileg elismert csillagász szakember, intézményvezető tudománymenedzser és egyben a média által kedvelt ismeretterjesztő tudós. Milyen impulzusok értek a falusi ég alatt, az inspiráló középiskolában és végül az egyetemen, ahol végképp eldőlt a szakmai sorsom? Mi kell ahhoz, hogy valaki helyt álljon bárhol a világban? Az életút mellett kitérek friss kutatásaimra a Naprendszerben és a más csillagok körül keringő bolygórendszerekben, földi és űrtávcsöves megfigyeléseken alapuló vizsgálataimra. Továbbá megosztom tapasztalataimat arról is, hogy a 21. században milyen módszerekkel lehet hatékonyan közvetíteni a tudományt, és hogyan kelthetjük fel az emberek, különösen a fiatalok érdeklődését a tudomány szépségei iránt.