SwePub
Tyck till om SwePub Sök här!
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Ruud Kenneth) "

Sökning: WFRF:(Ruud Kenneth)

  • Resultat 1-10 av 29
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Advances in Quantum Chemistry. vol 81 : Chemical Physics and Quantum Chemistry
  • 2020
  • Samlingsverk (redaktörskap) (refereegranskat)abstract
    • This volume collects 11 selected papers from the scientific contributions presented at the 10th Congress of the International Society for Theoretical Chemical Physics (ISTCP-X), organized by a team led by Professor Kenneth Ruud at the University of Tromsø—The Arctic University of Norway, from July 11 to 17, 2019. The ISTCP-X Congress in Tromsø followed the format established at the nine previous meetings:ISTCP-I: Professor Ramon Carbo-Dorca, Girona (Spain), June 28–July 3, 1993ISTCP-II: Professor Sean P. McGlynn, New Orleans (LA, USA), April 9–13, 1996ISTCP-III: Professor Miguel Castro, Mexico City (DF, Mexico), November 8–13, 1999ISTCP-IV: Professor Jean Maruani, Marly-le-Roi (Paris, France), July 9–16, 2002ISTCP-V: Professor Peter Politzer, New Orleans (LA, USA), July 20–26, 2005ISTCP-VI: Professor Yan Alexander Wang, Vancouver (BC, Canada), July 19–24, 2008ISTCP-VII: Professor Hiromi Nakai, Waseda (Tokyo, Japan), September 2–8, 2011ISTCP-VIII: Professor Péter Surján, Eötvös (Budapest, Hungary), August 25–31, 2013ISTCP-IX: Professor Mark Hoffmann, Grand Forks (ND, USA), July 17–22, 2016For the 10th congress of the ISTCP, there were 543 participants from all around the world. The program consisted of 200 lectures and almost 280 poster presentations, allowing the participants to get a broad view of the most recent advances in almost all subject matters in the field of theoretical chemical physics. With the city of Tromsø being located north of the Arctic Circle, the sun never set during the entire conference, creating a unique and stimulating atmosphere for scientific discussions.The International Society for Theoretical Chemical Physics (ISTCP) was founded in 1990 by Professor János Ladik at the University of Erlangen, Germany. ISTCP has the objectives to promote theoretical developments at the frontier between physics and chemistry. Additionally the goal is to allow younger researchers to interact with leading contributors in the field at regularly organized International Congresses. The Society involves an Honorary Board, a Board of Directors gathering altogether about 60 scientists (including five Nobel Laureates and two Wolf Prize laureates) in the fields of Theoretical Chemistry and Physics, and a Board of National Representatives covering about 35 countries/regions. The current President, since July 2000, is Professor Erkki J. Brändas, from Uppsala University, Sweden.ISTCP congress proceedings have been published regularly in the special issues of the International Journal of Quantum Chemistry (IJQC) and partly (2002, 2008) copublished in special volumes of Progress in Theoretical Chemistry and Physics (PTCP). For the 10th congress, we are very happy to be able to collect a small sample of the science presented at the ISTCP-X as a collection in Advances in Quantum Chemistry. These articles were solicited from researchers in several forefront fields represented at ISTCP-X.The articles cover topics from very accurate calculations using multireference perturbation theories and high-accuracy studies going beyond the Born-Oppenheimer approximation, through the study of interaction of light with molecules and materials—from very short attosecond processes to photophysical processes in chemical and biological systems—to the nature of excited states in anionic systems and the temperature dependence of the mobility of rubrene. Parity violation, fundamental symmetries, and tunneling effects are also covered and the power of machine learning in quantum chemistry is addressed in other chapters. Finally, Maximillian Seel provides some reminiscences of the founder of the ISTCP, Prof. Janos Ladik, who sadly passed away on March 17, 2018.ISTCP-X was organized into 13 thematic symposia, plus a special symposium honoring the late founder of the ISTCP, Prof. Janos Ladik, organized into a set of plenary and keynote lectures as well as parallel sessions covering contributions from the thematic symposia. The very compact conference venue made conversation across disciplines and thematic symposia easy to organize. The coorganizers of each of the symposia had significant freedom in inviting leading scientists in their areas, with attention paid to overall geographical, career stage, and gender balance. It is the careful thought and hard work of the Symposium Organizers that contributed to the success of the congress. The Symposia and their Organizers were:1.From picoseconds to attoseconds: nuclear and electron dynamics (David Clary, Leticia Gonzalez, Fernando Martin)2.Aspects of heavy-element chemistry (Pekka Pyykkö, Trond Saue)3.Emergent electronic structure methods (Stefan Goedecker, Gustavo Scuseria)4.Multiscale modeling including focused models (Benedetta Mennucci, Lyudmila Slipchenko)5.Large-scale electronic structure models of materials (Thomas Heine, Hiromi Nakai)6.Ultracold chemical physics (Jeremy M. Hutson, Bogumil Jeziorski)7.Molecular properties and interactions (Antonio Rizzo, Krzysztof Szalewicz)8.Computational spectroscopy: From X-rays to microwaves (Attila Csaszar, Hans Ågren)9.90 years of r12: Hylleraas symposium (Wim Klopper, Ed Valeev)10.Machine-learning and data-driven approaches in chemical physics (Alán Aspuru-Guzik, Pavlo Dral)11.Computational biophysics (Fernanda Duarte, Ursula Röthlisberger)12.Path-integral methods (David E. Manolopoulos, Gregory Voth)13.Physical organic chemistry and catalysis (Odile Eisenstein, Vidar R. Jensen)14.Janos Ladik memorial symposium (Erkki Brändas, Kenneth Ruud)In addition to symposia, there were 12 plenary and keynote talks for which all participants were gathered.1.Sharon Hammes-Schiffer, Multicomponent Quantum Chemistry: Integrating Electronic and Nuclear Quantum Effects2.Trygve Helgaker, Egil Hylleraas—A Pioneer of Computational Quantum Mechanics3.Peter Schwerdtfeger, The Year of the Periodic Table—Going Superheavy4.Sylvio Canuto, Environment Contribution to Molecular Spectroscopy, Reactivity and Photochemistry5.Peter Gill, Q-MP2-OS: A New Approach to Correlation Using Quadrature6.Peter Saalfrank, Molecules Driven by Light: Electron and Nuclear Dynamics7.Thomas F. Miller, Classical and Machine-Learning Methods for Quantum Simulation8.Irene Burghardt, High-Dimensional Quantum Dynamics of Functional Organic Polymer Materials: Coherence, Confinement, and Disorder9.Giulia Galli, Simulating Energy Conversion Processes From First Principles10.Zhigang Shuai, Density Matrix Renormalization Group: Time-Dependent Formalism, Light-Emitting, Carrier Transport, and Singlet Fission11.Monica Olvera de la Cruz, Properties of Molecular Electrolytes12.Kersti Hermansson, OH, Seriously, … Molecules + Materials = Difficult!We are grateful to all organizers for their exceptional work. We are indebted to our excellent scientific organizing committee that guided us in producing a well-balanced, global perspective on cutting-edge chemical physics: Aurora Clark, David Clary, Hazel Cox, Peter Gill, Leticia Gonzalez, Kersti Hermansson, Bogumil Jeziorski, Anna Krylov, Shuhua Li, Hiromi Nakai, Oleg Prezhdo, and Thereza Soares, and the local organizing committee: Maarten Beerepoot, Bjørn-Olav Bransdal, Stig Eide, Luca Frediani, Bin Gao, Stephanie Hansen, Kathrin Hopmann, and Michal Repisky. Many thanks also to Karen Dundas for designing the logo of the congress. We are also grateful to all session chairs, speakers, poster presenters, as well as all student volunteers, contributing significantly to the great success of the meeting. For more details regarding the congress we refer to the web site of the congress, http://istcp-2019.org/.The ISTCP-X congress took place at the Clarion Hotel The Edge in downtown Tromsø, located less than 5 km away from the local airport. The compact city center made it easy for participants to engage in discussions in restaurants and cafes, and gave a sense of a workshop with time and space for scientific discussions despite the large number of conference participants. The beautiful surroundings of the city and the never-ending days was exploited by many of the participants, who used the late evenings or early mornings to explore the surroundings through bicycle or hiking trips.We are pleased to express our sincere thanks to our sponsors. We would here in particular like to thank the Research Council of Norway and the University of Tromsø—The Arctic University of Norway for very generous financial support, and the staff at Clarion Hotel The Edge for making sure all practical aspects of the conference went smoothly. We are also grateful to ACS Omega, Journal of Chemical Theory and Computation, The Journal of Physical Chemistry, The Journal of Physical Chemistry Letters, PCCP, International Journal of Quantum Chemistry, Journal of Computational Chemistry, and Elsevier through Advances in Quantum Chemistry for providing poster awards for young researchers. The poster prize winners were selected by the members of the scientific committee, and we are grateful to our sponsors for allowing us to honor many young scientists for their excellent poster contributions at the conference.The guest editors of this special volume, finally, want to thank the authors, who accepted our invitation to contribute to these proceedings, and in so doing provide a perspective of some cutting-edge areas of study in chemical physics. The Xth congress of ISTCP included both these areas and many more. We hope that all researchers with a great interest in theory and methods related to fundamental scientific problems and future progress in our field will appreciate this volume.
  •  
2.
  • Aidas, Kestutis, et al. (författare)
  • Gauge-origin independent magnetizabilities from hybrid quantum mechanics/molecular mechanics models: Theory and applications to liquid water
  • 2007
  • Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614. ; 442:4-6, s. 322-328
  • Tidskriftsartikel (refereegranskat)abstract
    • The theory of a hybrid quantum mechanics/molecular mechanics (QM/MM) approach for gauge-origin independent calculations of the molecular magnetizability using Hartree-Fock or Density Functional Theory is presented. The method is applied to liquid water using configurations generated from classical Molecular Dynamics simulation to calculate the statistical averaged magnetizability. Based on a comparison with experimental data, treating only one water molecule quantum mechanically appears to be insufficient, while a quantum mechanical treatment of also the first solvation shell leads to good agreement between theory and experiment. This indicates that the gas-to-liquid phase shift for the molecular magnetizability is to a large extent of non-electrostatic nature. (c) 2007 Elsevier B.V. All rights reserved.
  •  
3.
  • Aidas, Kestutis, et al. (författare)
  • Solvent effects on NMR isotropic shielding constants. A comparison between explicit polarizable discrete and continuum approaches
  • 2007
  • Ingår i: The Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory. - : American Chemical Society (ACS). - 1520-5215. ; 111:20, s. 4199-4210
  • Tidskriftsartikel (refereegranskat)abstract
    • The gas-to-aqueous solution shifts of the O-17 and C-13 NMR isotropic shielding constants for the carbonyl chromophore in formaldehyde and acetone are investigated. For the condensed-phase problem, we use the hybrid density functional theory/molecular mechanics approach in combination with a statistical averaging over an appropriate number of solute-solvent configurations extracted from classical molecular dynamics simulations. The PBE0 exchange-correlation functional and the 6-311++G(2d,2p) basis set are used for the calculation of the shielding constants. London atomic orbitals are employed to ensure gauge-origin independent results. The effects of the bulk solvent molecules are found to be crucial in order to calculate accurate solvation shifts of the shielding constants. Very good agreement between the computed and experimental solvation shifts is obtained for the shielding constants of acetone when a polarizable water potential is used. Supermolecular results based on geometry-optimized molecular structures are presented. We also compare the results obtained with the polarizable continuum model to the results obtained using explicit MM molecules to model the bulk solvent effect.
  •  
4.
  • Aidas, Kestutis, et al. (författare)
  • The Dalton quantum chemistry program system
  • 2014
  • Ingår i: Wiley Interdisciplinary Reviews. Computational Molecular Science. - : Wiley. - 1759-0876. ; 4:3, s. 269-284
  • Tidskriftsartikel (refereegranskat)abstract
    • Dalton is a powerful general-purpose program system for the study of molecular electronic structure at the Hartree-Fock, Kohn-Sham, multiconfigurational self-consistent-field, MOller-Plesset, configuration-interaction, and coupled-cluster levels of theory. Apart from the total energy, a wide variety of molecular properties may be calculated using these electronic-structure models. Molecular gradients and Hessians are available for geometry optimizations, molecular dynamics, and vibrational studies, whereas magnetic resonance and optical activity can be studied in a gauge-origin-invariant manner. Frequency-dependent molecular properties can be calculated using linear, quadratic, and cubic response theory. A large number of singlet and triplet perturbation operators are available for the study of one-, two-, and three-photon processes. Environmental effects may be included using various dielectric-medium and quantum-mechanics/molecular-mechanics models. Large molecules may be studied using linear-scaling and massively parallel algorithms. Dalton is distributed at no cost from for a number of UNIX platforms.
  •  
5.
  • Badri, Zahra, et al. (författare)
  • All-Metal Aromaticity : Revisiting the Ring Current Model among Transition Metal Clusters
  • 2013
  • Ingår i: Journal of Chemical Theory and Computation. - : American Chemical Society (ACS). - 1549-9618 .- 1549-9626. ; 9:11, s. 4789-4796
  • Tidskriftsartikel (refereegranskat)abstract
    • We present new insight into the nature of aromaticity in metal clusters. We give computational arguments in favor of using the ring-current model over local indices, such as nucleus independent chemical shifts, for the determination of the magnetic aromaticity. Two approaches for estimating magnetically induced ring currents are employed for this purpose, one based on the quantum theory of atoms in molecules (QTAIM) and the other where magnetically induced current densities (MICD) are explicitly calculated. We show that the two-zone aromaticity/antiaromaticity of a number of 3d metallic clusters (Sc-3(-), Cu-3(+), and Cu-4(2-)) can be explained using the QTAIM-based magnetizabilities. The reliability of the calculated atomic and bond magnetizabilities of the metallic clusters are verified by comparison with MICD computed at the multiconfiguration self-consistent field (MCSCF) and density functional levels of theory. Integrated MCSCF current strength susceptibilities as well as a visual analysis of the calculated current densities confirm the interpretations based on the QTAIM magnetizabilities. In view of the new findings, we suggest a simple explanation based on classical electromagnetic theory to explain the anomalous magnetic shielding in different transition metal clusters. Our results suggest that the nature of magnetic aromaticity/antiaromaticity in transition-metal clusters should be assessed more carefully based on global indices.
  •  
6.
  • Bauer, Paul (författare)
  • Computational modelling of enzyme selectivity
  • 2017
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Enantioselective reactions are one of the ways to produce pure chiral compounds. Understanding the basis of this selectivity makes it possible to guide enzyme design towards more efficient catalysts. One approach to study enzymes involved in chiral chemistry is through the use of computational models that are able to simulate the chemical reaction taking place. The potato epoxide hydrolase is one enzyme that is known to be both highly enantioselective, while still being robust upon mutation of residues to change substrate scope. The enzyme was used to investigate the epoxide hydrolysis mechanism for a number of different substrates, using the EVB approach to the reaction both in solution and in several enzyme variants. In addition to this, work has been performed on new ways of performing simulations of divalent transition metals, as well as development of new simulation software.
  •  
7.
  • Botvinik-Nezer, Rotem, et al. (författare)
  • Variability in the analysis of a single neuroimaging dataset by many teams
  • 2020
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 582, s. 84-88
  • Tidskriftsartikel (refereegranskat)abstract
    • Data analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses(1). The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data. This flexibility resulted in sizeable variation in the results of hypothesis tests, even for teams whose statistical maps were highly correlated at intermediate stages of the analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Notably, a meta-analytical approach that aggregated information across teams yielded a significant consensus in activated regions. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset(2-5). Our findings show that analytical flexibility can have substantial effects on scientific conclusions, and identify factors that may be related to variability in the analysis of functional magnetic resonance imaging. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for performing and reporting multiple analyses of the same data. Potential approaches that could be used to mitigate issues related to analytical variability are discussed. The results obtained by seventy different teams analysing the same functional magnetic resonance imaging dataset show substantial variation, highlighting the influence of analytical choices and the importance of sharing workflows publicly and performing multiple analyses.
  •  
8.
  •  
9.
  • Chen, Xing, et al. (författare)
  • Zero-point vibrational corrections to isotropic hyperfine coupling constants in polyatomic molecules
  • 2011
  • Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : RSC Publishing. - 1463-9076 .- 1463-9084. ; 13:2, s. 696-707
  • Tidskriftsartikel (refereegranskat)abstract
    • The present work addresses isotropic hyperfine coupling constants in polyatomic systems with a particular emphasis on a largely neglected, but a posteriori significant, effect, namely zero-point vibrational corrections. Using the density functional restricted-unrestricted approach, the zero-point vibrational corrections are evaluated for the allyl radical and four of its derivatives. In addition for establishing the numerical size of the zero-point vibrational corrections to the isotropic hyperfine coupling constants, we present simple guidelines useful for identifying hydrogens for which such corrections are significant. Based on our findings, we critically re-examine the computational procedures used for the determination of hyperfine coupling constants in general as well as the practice of using experimental hyperfine coupling constants as reference data when benchmarking and optimizing exchange-correlation functionals and basis sets for such calculations.
  •  
10.
  • Ferrighi, Lara, et al. (författare)
  • Density-functional-theory study of the electric-field-induced second harmonic generation (EFISHG) of push-pull phenylpolyenes in solution
  • 2006
  • Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614 .- 1873-4448. ; 425:4-6, s. 5593-5603
  • Tidskriftsartikel (refereegranskat)abstract
    • Density-functional theory and the polarizable continuum model have been used to calculate the electric-field-induced second harmonic generation of a series of push-pull phenylpolyenes in chloroform solution. The calculations have been performed using both the Becke 3-parameter Lee-Yang-Parr functional and the recently developed Coulomb-attenuated method functional. Solvation has been investigated by examining the effects of the reaction field, non-equilibrium solvation, geometry relaxation, and cavity field. The inclusion of solvent effects leads to significantly better agreement with experimental observations.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 29
Typ av publikation
tidskriftsartikel (23)
annan publikation (2)
doktorsavhandling (2)
samlingsverk (redaktörskap) (1)
bokkapitel (1)
Typ av innehåll
refereegranskat (25)
övrigt vetenskapligt/konstnärligt (4)
Författare/redaktör
Ruud, Kenneth (25)
Ågren, Hans (10)
Rinkevicius, Zilvina ... (7)
Kongsted, Jacob (7)
Vahtras, Olav (4)
Norman, Patrick (4)
visa fler...
Mikkelsen, Kurt V. (4)
Bast, Radovan (4)
Luo, Yi (3)
Aidas, Kestutis (3)
Nielsen, Christian B ... (3)
Christiansen, Ove (3)
Coriani, Sonia (3)
Ferrighi, Lara (3)
Ekstrom, Ulf (2)
Fliegl, Heike (2)
Frediani, Luca (2)
Natarajan Arul, Muru ... (1)
Bauer, Paul (1)
Nilsonne, Gustav (1)
Botvinik-Nezer, Rote ... (1)
Dreber Almenberg, An ... (1)
Holzmeister, Felix (1)
Huber, Juergen (1)
Johannesson, Magnus (1)
Kirchler, Michael (1)
Poldrack, Russell A. (1)
Schonberg, Tom (1)
Sernelius, Bo (1)
Brändas, Erkki, Prof ... (1)
Tinghög, Gustav, 197 ... (1)
Glerean, Enrico (1)
Li, Xin (1)
Kauczor, Joanna (1)
Mo̸gelho̸j, Andreas (1)
Olsen, Jogvan Magnus ... (1)
Kjaer, Hanna (1)
Angeli, Celestino (1)
Bak, Keld L. (1)
Bakken, Vebjorn (1)
Boman, Linus (1)
Cimiraglia, Renzo (1)
Dahle, Pal (1)
Dalskov, Erik K. (1)
Enevoldsen, Thomas (1)
Eriksen, Janus J. (1)
Ettenhuber, Patrick (1)
Fernandez, Berta (1)
Hald, Kasper (1)
Halkier, Asger (1)
visa färre...
Lärosäte
Kungliga Tekniska Högskolan (19)
Lunds universitet (5)
Uppsala universitet (4)
Linköpings universitet (3)
Stockholms universitet (1)
Handelshögskolan i Stockholm (1)
visa fler...
Karolinska Institutet (1)
visa färre...
Språk
Engelska (29)
Forskningsämne (UKÄ/SCB)
Naturvetenskap (25)
Medicin och hälsovetenskap (1)
Samhällsvetenskap (1)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy