Working Groups

COSY Cost action

COSY Cost action

This COST Action aims to provide a computationally and experimentally sound foundation for the fundamental understanding and control of confined molecular systems. The resulting outcome will be translated into useful knowledge forming the basis for applications. These range from creating a new generation of materials including bio-materials, with immediate transfer to industry, to disclosing the chemistry occurring in space. COSY will tackle these and other challenges through 5 strongly correlated work packages:

1. Accurate description of the intermolecular interaction between a molecule and its confining environment through modern first principles tools.

2. Efficient description of molecular motion in confined structures, including coarse-grained, atomistic, and meso-scale molecular dynamics of metal-organic frameworks and biomolecular environments.

3. Synthesis and characterization of the stability and novel properties of metal and metal-oxide nanoparticles and subnanometric clusters for applications such as luminescence, sensing, bio-imaging, theranostics, energy conversion, and (photo-)catalysis.

4. Synthesis, deposition, and properties screening of high-purity innovative nanomaterials, using the very cold and practically inert environment provided by superfluid helium nanodroplets.

5. Accurate characterization of phenomena of astrochemical relevance such as the chemistry and physics occurring on the confining surface of interstellar clouds, using the most advanced spectroscopic techniques, and the highest level ab initio theories and methods for quantum nuclear motion.

WG1 - Intermolecular Interactions - Ab initio-Generated Force Fields and Machine Learning

Consists on defining the application ranges of established electronic structure methods for confined molecular systems, on new developments in electronic structure theory to characterize them, and on Machine Learning (ML)-based representations of the involved intermolecular interactions and applications. The meeting will cover the presentation of:

1) Theoretical tools aiming to calculate interaction potentials between molecular systems and complex environments, and between themselves, through a combination of high-level ab initio theories, state-of-the-art (e.g., dispersion-corrected and dispersion-less) density functional theory methods, and semi-empirical approaches.

2) New developments in electronic structure theory and ML-based representations of intermolecular interactions and applications. The focus will be on open-shell symmetry-adapted perturbation theory and highly accurate composite schemes to be used for benchmarking purposes.

3) Systematic density-functional-theory simulations for selected confined molecular systems and enhanced by machine-learning-parametrized force fields and algorithms to screen the most relevant energy potential landscapes, also validating and refining the DFT predictions on the basis of high-level ab initio results.

Deals with the testing and application of computational methods addressing confined molecular motion in large structures, including molecular cages, surfaces, and interfaces, combined with experimental characterizations. The meeting will cover the following topics related to the goals of the Action:

1) High-level ab initio calculations and grand-canonical Monte Carlo simulations for studying gas-surface and gas-gas interactions in microporous adsorbents. Testing and application of computational methods addressing confined molecular motion in large structures including molecular cages, surfaces, and interfaces, combined with experimental characterizations. The selection and design of improved materials for gas storage and adsorptive separation requires accurate determination of thermodynamic functions and reliable prediction of (co-)adsorption isotherms. The goal is not only the development of new materials and characterization of their adsorption properties but also benchmarking existing computational methods.

2) Molecular Dynamics of biomolecules in confined environments. New protocols to study the effect of the molecular crowding on the structure and dynamics of biological macromolecules (nucleic acids and proteins) and small binders found in the living cells by using quantum and classical approaches will be presented.  Assessing the effects of confinement on nucleic acids is of fundamental importance in many processes: from understanding the highly packed organization of the genetic material in the cell nucleus to gene delivery.

3) Quantum dynamics, spectroscopy, and reactivity of molecules interacting with electromagnetic fields. Apart from molecular structures, confinement may also be achieved by electromagnetic fields. An example are optical cavities, where molecules may become trapped, which gives rise to exciting possibilities of controlled probing of single molecules.  Interaction with electromagnetic fields often induces complicated coupled nuclear-electronic motion, the understanding of which requires the development of accurate and efficient methods for nonadiabatic dynamics.

Is focused on small metal and metal oxide nanoparticles in the size regime below 10 nm, where quantum confinement influences the system functionality. It is the regime of catalysis, photonics, and bio-sensing and thus connects directly with the world of technology, especially SMEs. The meeting will cover:

1) Recent advances in synthesis and surface-deposition of metal and metal/oxide nanoparticles and clusters from several nanometer-size nanoparticles to intermediate (1-4 nanometers) and subnanometer scale all the way to single metal atoms. Research on suitable combinations of materials, optimal size, structure and composition of nanoparticles and clusters for specific applications.

2) Experimental and theoretical characterization of the structural, physico-chemical, colloidal, magnetic, optoelectronic properties and (photo-)reactivity of novel nanomaterials linked to specific applications, such as (photo-) catalysis, sensing, imaging and bio-medicine. The objective is to establish correlations between the atomic architectures, confined electronic structures, and functional behaviour. The systems will be distinguished according to their environment: deposited on a substrate (including the influence of the cluster/support interaction) vs. in solution and including their interaction with (bio-)molecules.

3) High-level ab initio descriptions and experimental assessment. Theoretical descriptions in different confining environments (supported in materials, air, solution, and biologically relevant environments, with and without light) by combining high-level ab initio and embedding approaches will be discussed.

 

4) Identification of priority areas on which synergistic efforts of the participants to the WG3 of the Action could be concentrated, based especially on the availability of effective techniques for the synthesis, the experimental characterization, and the theoretical modeling of the static and dynamic structure, as well as the opto-electronic and functional (e.g., catalytic) properties of the systems.

Deals with helium nanodroplets as unique nano-cryo reactors for aggregating, cooling, and probing molecular complexes, metallic clusters and exotic nanoparticles. The structure and dynamics of both the embedded aggregates and of the quantum fluid helium nanodroplets are experimentally probed by IR, high-resolution and time-resolved laser spectroscopy, mass spectrometry, charged-particle imaging, single-particle x-ray diffraction imaging, and surface deposition. Helium nanodroplets impacting a surface allows the realization of `soft-landing deposition’, that is transferring embedded aggregates from the quantum liquid droplets onto substrates with minimal structure changes. Theoretical tools will combine quantum [(time-dependent) density functional theory], semiclassical and classical methods for the He atom motion. This first meeting will address specific systems produced by helium-droplet-mediated synthesis and surface deposition: (i) multi-component metal and metal-oxide clusters, nanoparticles, and single atoms; (ii) nano-aggregates probed in situ by x-ray coherent diffraction imaging; iii) organic (donor-acceptor) light-harvesting complexes; (iv) solvated, microhydrated molecules and organic complexes relevant for biology; (v) hydrocarbon clusters and molecules forming prebiotic species at star-dust conditions.

Focuses in Astrochemistry in a broad sense. Observations both from the interstellar medium and laboratory experiments form the basis for the computational and theoretical chemistry and physics methods.

1) The experimental methods at our disposal play an important role, i.e., attractive kinetics and spectroscopy experiments in the laboratory, often mimicking at least partly the conditions in the interstellar medium. The spectroscopy part includes the state-of-the-art laser experiments with frequency combs and build-up cavities. Kinetics and dynamics experiments that use modern spectroscopy tools will be directed particularly to low temperature and barrierless reactions appropriate for interstellar medium.

2)  Fascinating quantum chemistry and classical physics computational tools have to cope with the gas systems of isolated molecules with high precision and the complexity of the surface and condensed phase systems. We are interested in using and developing these methods in investigating molecular properties and chemical reactions in the gas and condensed phase molecular problems in astrochemistry. Extreme conditions such as very large magnetic fields and high temperatures will also play a role in applying theory and computational approaches.

3) As all these issues are demanding but very interesting and scientifically stimulating, the other members in COSY are very welcome to share their scientific knowhow with the WG5 members.