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Density Functional Theory

  • A trip to the Density Functional Theory Zoo

    Speaker: Dr Lars Goerigk
    Institute: The University of Melbourne
    Country: Australia
    Speaker Link: https://goerigk.chemistry.unimelb.edu.au/

    Dr Lars Goerigk

    Melbourne Centre for Theoretical and Computational Chemistry,
    School of Chemistry, The University of Melbourne, VIC 3010, Australia


    Video Recording

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    Abstract

    The importance of Density Functional Theory (DFT) to the chemical sciences is well known. However, despite today’s easy access to DFT software packages to everyone, there remains a large communication gap between DFT developers and users that has resulted in various misconceptions and the regular application of outdated procedures. One reason for this is the fact that there is not only one manifestation of DFT, but hundreds of approximations to the true, unknown functional. Naturally, not only users that are new to the field, but also experts can find this ever-growing `zoo’ of DFT approximations confusing.

    This presentation provides an overview of the zoo of DFT methods and is suitable to both students that are new to the field and more experienced researchers. Rather than spending too much time on discussing the physical/mathematical foundation of DFT, I will focus on aspects that are relevant to computational applications with guidelines and recommendations as take-home messages that may assist in future research endeavours. After a short overview of the basic idea of DFT and Perdew’s famous Jacob’s Ladder classification of DFT approximations, I will cover how we can identify the best and most robust representatives of the zoo for applications to thermochemistry and kinetics. A special emphasis will be given to the importance of London-dispersion interactions. Towards the end, more specialised aspects will be discussed that may be of interest to more theoretically oriented viewers.

     

  • Ask ERCEA officers: a roundtable discussion on career development and ERC funding opportunities

    Speaker: Dr. Janka Mátrai
    Institute: European Research Council
    Country: Belgium
    Speaker Link: https://be.linkedin.com/in/janka-m%C3%A1trai-1685b920
    Speaker: Dr. Balázs Pinter
    Institute: European Research Council
    Country: Belgium
    Speaker Link: https://www.linkedin.com/in/balazs-pinter-b8611a92
    Time: 11:00 CET 30-Jan-24

    Dr Janka Mátrai and Dr Balázs Pinter

    Scientific Project Adviser at The Executive Agency of the European Research Council

    Janka Mátrai is a scientific project adviser at the ERCEA - The Executive Agency of the European Research Council (ERC), in the Life Sciences Unit. She is responsible for managing the whole life cycle
    of grant application, evaluation and follow-up processes in two panels, Integrative Biology: From Genes and Genomes to Systems, and Neuroscience and Disorders of the Nervous System,
    respectively. She is also involved in the widening participation campaign, which aims to close the gap between the Widening European Participation countries and the rest of the EU. Prior to this, she
    worked as a scientific project officer at the Joint Research Centre – Institute for Reference Materials and Measurements in the Standards for Innovation and Sustainable Development, Reference
    Materials for Biotechnology and Life Sciences Unit, where she was managing the production of certified DNA reference materials.
    After graduating from the Budapest University of Technology and Economics as a bioengineer, Janka obtained her PhD degree in Biochemistry and Bioinformatics at the Catholic University of Leuven
    (KUL), after which she continued with scientific research as a postdoctoral scientist in areas of Molecular Modelling and Drug Design, and Fundamental and Translational Medical Research, Gene
    Therapy and Regenerative Medicine at the Flanders Institute for Biotechnology (VIB) and the Free University of Brussels (VUB).
    In this session, Janka will discuss some important factors that shaped her career path. She will also share her experience with scholarships and grant applications, highlighting some dos and don’ts.

    Balazs Pinter recently joined the Physical Sciences and Engineering Unit of ERCEA – The Executive Agency of the European Research Council – as a scientific project adviser, where he is involved in all
    aspects of the implementation of ERC’s work programme, from the evaluation of proposal to the follow-up of projects in both chemistry panels of the agency: Physical and Analytical Chemical
    Sciences and Synthetic Chemistry and Materials. 
    Before joining ERCEA, Dr. Pinter was an assistant professor at The University of Texas at El Paso where he headed the Computational OrganoMetallic and Inorganic Chemistry (COMIC) research
    group with a research activity centred at the (photo)redox chemistry of transition metal complexes, and the rational engineering of their electrochemical properties via computational means, especially
    density functional theory (DFT) based methods, amongst others. Prior experiences include professorships in Chile and Belgium and various postdoc positions at Indiana University Bloomington,
    Duke University, Vrije Universiteit Brussel and research visits at University of Girona and Max-Planck Institute for Chemical Energy conversion. Dr. Pinter holds a PhD in Chemistry and an MSc in Chemical
    Engineering from Budapest University of Technology and Economics, Hungary. 
    In this session, Dr. Pinter will discuss the potential effect of omnipresent academic notions, such as ‘publish or perish’ and ‘red flags’ on the scientific career and in hiring processes, review the DORA
    principles and Open Science practices and present the funding schemes of ERC. 

    Keywords: molecular modelling, drug design, gene therapy, certified DNA reference materials, scientific project management, Density Functional Theory, photoredox catalysis, redox active ligands, DORA principles,
    Open Science

     

    References:

    European Society for Gene and Cell Therapy, Ask the Expert career session. 
    The European Research Council’s online classes. 
    Editorial, Nature 535, 465 (2016). Agencies must show that basic research is worth the investment
    Mátrai, J, et al. (2015), Certification report. DNA Certified Refence Material
    Mátrai J, et al. (2012). J Genet Syndr Gene Ther, S:1. Lentiviral Gene Therapy for Haemophilia A and B
    Mátrai J*, Cantore A*, Bartholomae C*, et al. (2011). Hepatology, 53 (5),1696-707. *Equal
    contribution. Hepatocyte-targeted expression by integrase-defective lentiviral vectors
    Mátés L, et al. (2009). Nat Genet. 41 (6), 753-61. Novel hyperactive Sleeping Beauty transposase
    enables robust stable gene transfer in vertebrates
    Mátrai J, et al. (2010). Curr Opin Hematol. 17 (5), 387-92. Preclinical and clinical progress in
    haemophilia
    Mátrai J, et al. A Guide to Human Gene Therapy, 2010. A Guide to Human Gene Therapy

    Mátrai J, et al. (2008). Eur Biophys J. 38 (1), 13-23. The activation pathway of Δα-Chymotrypsin
    Le Roy K, et al. (2013). Plant Physiol. 161 (4), 1670-81. Defective Invertases in Plants: Tobacco Nin88
    Fails to Degrade Sucrose
    Mátrai J, et al. (2001). J. Org. Chem. 66 (17), 5671-5678. Mechanism of the Ring−Chain
    Rearrangement in Phosphiranes
    Veszprémi T, et al. (2001). THEOCHEM. 538 (1-3): 189-195. Lithium azaphospholide complexes
    A Science Club in Brussels. Belgian Club of Hungarian Scientists

    Sandoval-Pauker, C.; Pinter, B. “Electronic Structure Analysis of Copper Photoredox Catalysts
    Using the Quasi-Restricted Orbital Approach”, J. Chem. Phys., 2022, 157, 074306.
    Sandoval-Pauker, C.; Molina-Aguirre, G.; Pinter, B. “Status report on copper (I) complexes in
    photoredox catalysis; photophysical and electrochemical properties and future prospects.”
    Polyhedron, 2021, 199, 115105.
    Medina, E.; Pinter, B. “An electron density difference analysis on the oxidative- and reductive
    quenching cycles of classical iridium and ruthenium photoredox catalysts”, J. Phys. Chem. A, 2020,
    124, 4223–4234.
    Pinter, B.; Al-Saadon, R.; Chen, Z., Yang, W. “Spin-state energetics of iron(II) porphyrin from the
    particle-particle random phase approximation” Eur. Phys. J.B., 2018, 91, 270.
    Gazvoda, M.; Virant, M.; Pinter, B.; Košmrlj, J., “Mechanism of copper-free Sonogashira reaction
    operates through palladium-palladium transmetallation” Nat. Commun. 2018, 9, 4814.

    Recording:

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  • Beyond free energy profiles: Microkinetic modeling and other tricks

    Speaker: Prof. Dr. Feliu Maseras
    Institute: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Tarragona
    Country: Spain
    Speaker Link: https://www.iciq.org/research/research_group/prof-feliu-maseras/
    Time: 09:00 CET 29-Jan-24

    Prof. Dr Feliu Maseras

    Institute of Chemical Research of Catalonia (ICIQ), Tarragona, Catalonia, Spain

    Computational chemistry has focused historically in the struggle for the accurate calculation of free energy profiles. Continued progress in computer power and theoretical methods has led in recent years to a situation where these free energy profiles have become rather accurate, in particular in domains such as computational homogeneous catalysis [1]. Because of this, we can now focus on further refinements to bring calculation closer to experiment. One of these refinements is microkinetic modeling, which allows the introduction of the effect of concentrations [2,3].

    feliu pic

    The raw experimental results usually involve reaction times rather than the energy barriers emerging from the free energy profiles. Microkinetic models can make the connection between rate constants calculated from density functional theory (DFT) and reaction times.
    In this presentation we will briefly discuss the idea of the treatment, and present selected examples of application with COPASI, [4] one of the main codes freely available. Other extensions to free energy profiles, such as Marcus theory for single electron transfer steps will be be briefly discussed also.

    Keywords: Density Functional Theory, Microkinetic modeling, Homogeneous catalysis.

     

    References:

    [1] Harvey, J. N.; Himo, F.; Maseras, F.; Perrin, L. ACS Catal. 2019, 9, 6803-6813.
    [2] Besora, M.; Maseras, F. WIREs Comput. Mol. Sci. 2018, 8, e1372.
    [3] Sciortino, G.; Maseras, F. Top Catal. 2022, 65, 105-117.
    [4] https://copasi.org (accessed Dec 9 th , 2023).

    Recording:

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  • Methods for the prediction and analysis of electronic structures for magnetically coupled transition metal complexes

    Speaker: Professor Vera Krewald
    Institute: TU Darmstadt
    Country: Germany
    Speaker Link: https://www.chemie.tu-darmstadt.de/krewald/ak_krewald/prof_dr_vera_krewald/index.de.jsp

    Prof. Dr. Vera Krewald

    Technical University of Darmstadt, Department of Chemistry, Theoretical Chemistry Alarich-Weiss-Str. 4, 64287 Darmstadt, Germany

    Exchange coupling interactions between open-shell ions in polynuclear transition metal complexes define key magnetic and spectroscopic properties of these systems. The metal coordination environment, especially the bridging ligands, determine the nature and magnitude of the magnetic coupling. This lecture will introduce phenomenological models for the interpretation of experimental data and computational chemistry methods relevant to the prediction and analysis of magnetically coupled electronic structures. 

    Density functional theory (DFT), in particular broken-symmetry DFT (BS-DFT), is used routinely to predict the sign, strength and origin of magnetic coupling in transition metal complexes. The advantages and intrinsic limitations of BS-DFT will be discussed. 

    In contrast to BS-DFT, multireference quantum-chemical calculations are in principle capable of describing each individual spin state arising from magnetic coupling of open-shell ions. The use of density matrix renormalization group (DMRG) for the description of realistic systems with multiple centers and many unpaired electrons will be outlined. In addition, a simple analytic tool that permits the identification of exchange coupling pathways in polynuclear transition metal complexes from an entanglement analysis will be introduced.

    Recording:

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    References

    (i) F. E. Mabbs, D. J. Machin. Magnetism and Transition Metal Complexes. London: Chapman & Hall, 1973.

    (ii) J. P. Malrieu, R. Caballol, C. J. Calzado, C. de Graaf, N. Guihéry. ‘Magnetic Interactions in Molecules and Highly Correlated Materials: Physical Content, Analytical Derivation, and Rigorous Extraction of Magnetic Hamiltonians’. Chem. Rev. 114, 2014, 429–492. https://doi.org/10.1021/cr300500z

    (iii) D. A. Pantazis, V. Krewald, M. Orio, F. Neese. ‘Theoretical Magnetochemistry of Dinuclear Manganese Complexes: Broken Symmetry Density Functional Theory Investigation on the Influence of Bridging Motifs on Structure and Magnetism’. Dalton Trans. 39, 2010, 4959–4967. https://doi.org/10.1039/c001286f

    (iv) V. Krewald, F. Neese, D. A. Pantazis. ‘On the Magnetic and Spectroscopic Properties of High-Valent Mn3CaO4 Cubanes as Structural Units of Natural and Artificial Water-Oxidizing Catalysts’. J. Am. Chem. Soc. 135, 2013, 5726–5739. https://doi.org/10.1021/ja312552f

    (v) M. Roemelt, V. Krewald, D. A. Pantazis. ‘Exchange Coupling Interactions from the Density Matrix Renormalization Group and N-Electron Valence Perturbation Theory: Application to a Biomimetic Mixed-Valence Manganese Complex’. J. Chem. Theory Comput. 14, 2018, 166–179. https://doi.org/10.1021/acs.jctc.7b01035

    (vi) C. J. Stein, D. A. Pantazis, V. Krewald. ‘Orbital Entanglement Analysis of Exchange-Coupled Systems’. J. Phys. Chem. Lett. 10, 2019, 6762–6770. https://doi.org/10.1021/acs.jpclett.9b02417

  • Putting density functional theory to the test in machine-learning accelerated discovery for transition metal chemistry

    Speaker: Professor Heather Kulik
    Institute: MIT
    Country: USA
    Speaker Link: http://hjkgrp.mit.edu/

    Professor Heather J. Kulik

    Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA

    Many compelling functional materials and highly selective catalysts have been discovered that are defined by their metal-organic bonding. The rational design of de novo transition metal complexes however remains challenging. First-principles (i.e., with density functional theory, or DFT) high-throughput screening is a promising approach but is hampered by high computational cost, particularly in the brute force screening of large numbers of ligand and metal combinations. In this talk, I will describe how automation[1-3], machine learning[4-6] autonomous tool development[7], sensitivity analysis, and multireference character detection[8] can all be used to simultaneously overcome limitations in cost and accuracy of DFT-based screening in open shell transition metal chemistry. I will describe the basic approach of our automated workflow, molSimplify[1-3], for automating calculations as well as recent extensions of machine learning (ML) models that avoid direct calculation of not just energetic or structural properties but also the likelihood of a calculation to succeed or a complex[7] to contain strong correlation[8]. I will describe how unifying databases shed light on the sensitivity of discovery outcomes to underlying DFT functionals. I will discuss possibilities for accelerating discovery with ML[9] with awareness of uncertainty[10] when sampling new regions of chemical space. Time permitting, I will describe how this powerful toolkit has advanced our understanding of metal-organic bonding in materials far-ranging from functional spin crossover complexes to open-shell transition metal catalysts and metal-organic frameworks.

    Recording:

    References

    [1] Ioannidis, E. I.; Gani, T. Z. H.; Kulik, H. J. molSimplify: A Toolkit for Automating Discovery in Inorganic Chemistry. Journal of Computational Chemistry 2016, 37, 2106-2117.

    [2] molSimplify lite web interface: https://molsimplify.mit.edu

    [3] Kulik group github with molSimplify and MultirefPredict: https://github.com/hjkgrp

    [4] Janet, J. P.; Kulik, H. J. Resolving Transition Metal Chemical Space: Feature Selection for Machine Learning and Structure-Property Relationships. The Journal of Physical Chemistry A 2017, 121, 8939-8954.

    [5] Janet, J. P.; Liu, F.; Nandy, A.; Duan, C.; Yang, T.; Lin, S.; Kulik, H. J. Designing in the Face of Uncertainty: Exploiting Electronic Structure and Machine Learning Models for Discovery in Inorganic Chemistry. Inorganic Chemistry 2019, 58, 10592-10606.

    [6] Janet, J. P.; Kulik, H. J. Machine Learning in Chemistry. ACS InFocus Book Series. 2020.

    [7] Duan, C.; Janet, J. P.; Liu, F.; Nandy, A.; Kulik, H. J. Learning from Failure: Predicting Electronic Structure Calculation Outcomes with Machine Learning Models. Journal of Chemical Theory and Computation 2019, 15, 2331-2345.

    [8] Liu, F.; Duan, C.; Kulik, H. J. Rapid Detection of Strong Correlation with Machine Learning for Transition-Metal Complex High-Throughput Screening. The Journal of Physical Chemistry Letters 2020, 11, 8067-8076. 

    [9] Janet, J. P.; Ramesh, S.; Duan, C.; Kulik, H. J. Accurate Multiobjective Design in a Space of Millions of Transition Metal Complexes with Neural-Network-Driven Efficient Global Optimization. ACS Central Science 2020, 6, 513-524.

    [10] Janet, J. P.; Duan, C.; Yang, T.; Nandy, A.; Kulik, H. J. A Quantitative Uncertainty Metric Controls Error in Neural Network-Driven Chemical Discovery. Chemical Science 2019, 10, 7913-7922.