Konferenzservice Mandl

Zusammenfassung: Electronic structure and properties of atoms, molecules and clusters. New theoretical and computational developments.

Zusammenfassung: In addition to carbon and silicon, germanium, tin, and in part lead can form many functional and important nanostructures, nanocrystals, and nanoclusters, which can be further functionalized by tailoring suitable key-properties according to specific needs. Such systems, and in particular hollow structures such as nanotubes and nanocages, are currently of great interest in science and technology with applications ranging from optoelectronics to biotechnology.

Simple and mixed nanosystems such as silicon, carbon, germanium, silicon-carbon Fullerenes (cages) nanotubes and nanowires all the way to organometallic silicon and germanium structures, stannaspherene and plumbaspherene will be considered and the latest developments will be discussed and analyzed in this workshop. All theoretical, computational, or even experimental works related (directly or indirectly) with these topics are welcome.

Special emphasis will be placed on calculations and/or approaches which bring up the similarities and differences between various systems and methods, as well as on unifying principles and concepts relating these systems to each other and to other groups.

Zusammenfassung: This symposium will aim at bringing together computational chemists, computational physicists and methodology developers to discuss the state of the art in the description of magnetic systems with localized magnetic moments from first principles. This includes isolated molecular magnets and their crystals, magnetic oxides, cuprates and the recently discovered family of superconductors based on LaOFeAs. A few key lectures by well known experimental scientists will also contribute to close the gap between theory and experiment.

Zusammenfassung: The Symposium will concentrate on the theory of strong couplings between high and low-frequency vibrations, Davydov and Fermi resonances in hydrogen-bonded systems. Calculated bandshapes of IR and Raman spectra of hydrogen-bonded crystals, liquids and gaseous complexes will be compared with experimental spectra. Spectral analysis by infrared and Raman methods gives important information about structure and dynamics of systems with hydrogen bonds, between others about tunnelling processes, mechanisms of dissipation of energy, etc. Calculations of multidimensional potentials and dynamics of protons in hydrogen bridges will be presented. We will present results of theoretical simulations of experimental tunnelling splittings observed in spectra of hydrogen-bonded systems. Behaviour of water clusters as basic elements present in nature will be analyzed. Spectra of large assemblies of water, such as ice clusters and their surface properties will be simulated by quantum and model calculations.

Zusammenfassung: A changing climate, with potential 5 degrees increase within the next century, will lead to increasing destabilisation of natural gas hydrates around the world. The physical understanding of these reservoirs in terms of the non-equilibrium states, and different phase transitions which generate new hydrate as well as phase transitions which leads to dissociation requires multi-scale modelling approaches. Molecular dysnamics simulations can provide physical and thermodynamic properties for the individual phases as well as for the interfaces between. These simulations also provide detailed information on a limited scale but the simulations have to be linked to other conepts which are able to simulate dynamics of simultaenous and competing phase transitions on levels up to micro-scale. Examples of this type of approach is illustrated through the use of Phase Field Theory. The different levels in the modelling is discussed in detail and a final example on conversion of methane hydrate over to carbon dioxide hydrate is compared to fundamental experimental data.

Zusammenfassung: The Symposium will deal with molecular modeling of biological systems. Emphasis will be given to applications of quantum chemical methods to molecular medicine. These are increasingly faster and accurate, becoming a valuable tool in the search for active substances. These methods help study inhibitor binding, identifying the surface load of active substances or deriving molecular descriptors. In particular, density functional theory (DFT)-based molecular dynamics (MD) simulations hybrid molecular mechanics schemes have recently emerged as a powerful tool to provide structural and spectroscopic information on novel anticancer drugs that target DNA as well as to lead to mechanistic hypotheses for a variety of enzymes of pharmacological relevance. Recent advances that increase the accuracy of DFT and the efficiency of investigating rare events are further expanding the domain of applications of DFT/MD to medicinal chemistry.

Zusammenfassung: "Graphene" – a new carbonaceous material – is distinguished from conventional electronic systems such as graphite due to its exceptional features, e.g., a large magnetic moment around the zigzag edges and massless Dirac fermion, stimulating development of future electronic/spintronic devices. Several unique features of graphene are closely connected with the "open-shell character", which originates in the "instability of chemical bonds" in ?-conjugated system with unconventional spin states and strongly correlates with the topology of ?-electron array, especially aromatic sextet formation. This symposium focuses on recent hot topics regarding unique physical and chemical properties derived from pseudo and real spins in ?-conjugated compounds, toward collaboration between theory, computational modeling and experiment. A wide range of compounds from small conjugated/aromatic molecules and inorganic metal complexes to nano- and large-size graphenes will be covered, and origin of the open-shell character as well as functional properties such as electron conductivity, optical and magnetic properties will be concentrated as important domains in the symposium.

Zusammenfassung: Vibrational spectroscopy is a particularly powerful tool for non-destructive characterisation of molecular systems. Besides routine analysis in a wide range of domains (food science, archaeology, astrophysics, medicine), numerous applications in molecular science, such as speciation, conformational analysis, molecular design and reactivity monitoring, can be based on the modelling of vibrational effects.

In recent years computational chemistry provides powerful tools for the modelling of such properties in the gas, liquid and solid phase although anharmonicity, resonances, environmental and dynamic effects render the problem non-trivial.

Several computational aspects will be emphasised in the present symposium: the quality of the potential electronic surface, time-dependent and time-independent approaches to the study of vibration, the treatment of the condensed phases (solvent, surfaces and bulk), the computation of intensities and possible ways to overcome actual limitations due to the size of the treated systems.

The performance of modern methods will be critically reviewed and their relative merit.

Zusammenfassung: Endohedrally doped fullerenes or nano-structures in general have very interesting properties, (e.g. nonlinear optical response, superconductivity etc.) and various important applications in medicine and the development of novel materials. A variety of physical phenomena, such as confinement, charge transfer effects etc. modify, sometimes significantly, the properties of the cage and/or the “guest”. Thus, there is currently intensive research on them. This symposium will focus on theoretical and computational advances related with structure and properties of endohedral complexes.

Zusammenfassung: In the last decades the organo-metallic molecules have attracted considerable attention due to numerous applications such as, catalysis, materials science. This symposium would like to present recent advances on the computational techniques used to study a series of interesting properties and related problems of metal dithiolenes such as, nature of bonding, charge transfer effects, electronic structure and description of the ground state, in order to gain insight into structure-property relationships and spectral characteristics.