References of "Tkatchenko, Alexandre 50009596"      in Complete repository Arts & humanities   Archaeology   Art & art history   Classical & oriental studies   History   Languages & linguistics   Literature   Performing arts   Philosophy & ethics   Religion & theology   Multidisciplinary, general & others Business & economic sciences   Accounting & auditing   Production, distribution & supply chain management   Finance   General management & organizational theory   Human resources management   Management information systems   Marketing   Strategy & innovation   Quantitative methods in economics & management   General economics & history of economic thought   International economics   Macroeconomics & monetary economics   Microeconomics   Economic systems & public economics   Social economics   Special economic topics (health, labor, transportation…)   Multidisciplinary, general & others Engineering, computing & technology   Aerospace & aeronautics engineering   Architecture   Chemical engineering   Civil engineering   Computer science   Electrical & electronics engineering   Energy   Geological, petroleum & mining engineering   Materials science & engineering   Mechanical engineering   Multidisciplinary, general & others Human health sciences   Alternative medicine   Anesthesia & intensive care   Cardiovascular & respiratory systems   Dentistry & oral medicine   Dermatology   Endocrinology, metabolism & nutrition   Forensic medicine   Gastroenterology & hepatology   General & internal medicine   Geriatrics   Hematology   Immunology & infectious disease   Laboratory medicine & medical technology   Neurology   Oncology   Ophthalmology   Orthopedics, rehabilitation & sports medicine   Otolaryngology   Pediatrics   Pharmacy, pharmacology & toxicology   Psychiatry   Public health, health care sciences & services   Radiology, nuclear medicine & imaging   Reproductive medicine (gynecology, andrology, obstetrics)   Rheumatology   Surgery   Urology & nephrology   Multidisciplinary, general & others Law, criminology & political science   Civil law   Criminal law & procedure   Criminology   Economic & commercial law   European & international law   Judicial law   Metalaw, Roman law, history of law & comparative law   Political science, public administration & international relations   Public law   Social law   Tax law   Multidisciplinary, general & others Life sciences   Agriculture & agronomy   Anatomy (cytology, histology, embryology...) & physiology   Animal production & animal husbandry   Aquatic sciences & oceanology   Biochemistry, biophysics & molecular biology   Biotechnology   Entomology & pest control   Environmental sciences & ecology   Food science   Genetics & genetic processes   Microbiology   Phytobiology (plant sciences, forestry, mycology...)   Veterinary medicine & animal health   Zoology   Multidisciplinary, general & others Physical, chemical, mathematical & earth Sciences   Chemistry   Earth sciences & physical geography   Mathematics   Physics   Space science, astronomy & astrophysics   Multidisciplinary, general & others Social & behavioral sciences, psychology   Animal psychology, ethology & psychobiology   Anthropology   Communication & mass media   Education & instruction   Human geography & demography   Library & information sciences   Neurosciences & behavior   Regional & inter-regional studies   Social work & social policy   Sociology & social sciences   Social, industrial & organizational psychology   Theoretical & cognitive psychology   Treatment & clinical psychology   Multidisciplinary, general & others     Showing results 61 to 80 of 148     1 2 3 4 5 6 7 8     Wavelike charge density fluctuations and van der Waals interactions at the nanoscaleAmbrosetti, Alberto; Ferri, Nicola; DiStasio Jr., Robert A. et alin Science (2016), 351(6278), 1171-1176Recent experiments on noncovalent interactions at the nanoscale have challenged the basic assumptions of commonly used particle- or fragment-based models for describing van der Waals (vdW) or dispersion ... [more ▼]Recent experiments on noncovalent interactions at the nanoscale have challenged the basic assumptions of commonly used particle- or fragment-based models for describing van der Waals (vdW) or dispersion forces. We demonstrate that a qualitatively correct description of the vdW interactions between polarizable nanostructures over a wide range of finite distances can only be attained by accounting for the wavelike nature of charge density fluctuations. By considering a diverse set of materials and biological systems with markedly different dimensionalities, topologies, and polarizabilities, we find a visible enhancement in the nonlocality of the charge density response in the range of 10 to 20 nanometers. These collective wavelike fluctuations are responsible for the emergence of nontrivial modifications of the power laws that govern noncovalent interactions at the nanoscale. [less ▲]Detailed reference viewed: 816 (81 UL) Modeling quantum nuclei with perturbed path integral molecular dynamicsPoltavsky, Igor; Tkatchenko, Alexandre in Chemical Science (2016), 7(2), 1368-1372The quantum nature of nuclear motions plays a vital role in the structure, stability, and thermodynamics of molecules and materials. The standard approach to model nuclear quantum fluctuations in chemical ... [more ▼]The quantum nature of nuclear motions plays a vital role in the structure, stability, and thermodynamics of molecules and materials. The standard approach to model nuclear quantum fluctuations in chemical and biological systems is to use path-integral molecular dynamics. Unfortunately, conventional path-integral simulations can have an exceedingly large computational cost due to the need to employ an excessive number of coupled classical subsystems (beads) for quantitative accuracy. Here, we combine perturbation theory with the Feynman-Kac imaginary-time path integral approach to quantum mechanics and derive an improved non-empirical partition function and estimators to calculate converged quantum observables. Our perturbed path-integral (PPI) method requires the same ingredients as the conventional approach but increases the accuracy and efficiency of path integral simulations by an order of magnitude. Results are presented for the thermodynamics of fundamental model systems, an empirical water model containing 256 water molecules within periodic boundary conditions, and ab initio simulations of nitrogen and benzene molecules. For all of these examples, PPI simulations with 4 to 8 classical beads recover the nuclear quantum contribution to the total energy and heat capacity at room temperature within a 3 accuracy, paving the way toward seamless modeling of nuclear quantum effects in realistic molecules and materials. [less ▲]Detailed reference viewed: 250 (9 UL) Report on the sixth blind test of organic crystal structure prediction methodsReilly, Anthony M.; Cooper, Richard I.; Adjiman, Claire S. et alin Acta Crystallographica Section B (2016), 72(4), 439--459The sixth blind test of organic crystal structure prediction (CSP) methods has been held, with five target systems: a small nearly rigid molecule, a polymorphic former drug candidate, a chloride salt ... [more ▼]The sixth blind test of organic crystal structure prediction (CSP) methods has been held, with five target systems: a small nearly rigid molecule, a polymorphic former drug candidate, a chloride salt hydrate, a co-crystal and a bulky flexible molecule. This blind test has seen substantial growth in the number of participants, with the broad range of prediction methods giving a unique insight into the state of the art in the field. Significant progress has been seen in treating flexible molecules, usage of hierarchical approaches to ranking structures, the application of density-functional approximations, and the establishment of new workflows and `best practices' for performing CSP calculations. All of the targets, apart from a single potentially disordered Z$^\prime$ = 2 polymorph of the drug candidate, were predicted by at least one submission. Despite many remaining challenges, it is clear that CSP methods are becoming more applicable to a wider range of real systems, including salts, hydrates and larger flexible molecules. The results also highlight the potential for CSP calculations to complement and augment experimental studies of organic solid forms. [less ▲]Detailed reference viewed: 204 (4 UL) Adsorption of isophorone and trimethyl-cyclohexanone on Pd(111): A combination of infrared reflection absorption spectroscopy and density functional theory studiesDostert, Karl-Heinz; O'Brien, Casey P.; Liu, Wei et alin Surface Science (2016), 650Detailed reference viewed: 128 (0 UL) Communication: Many-body stabilization of non-covalent interactions: Structure, stability, and mechanics of Ag3Co(CN)6 frameworkLiu, Xiaofei; Hermann, Jan; Tkatchenko, Alexandre in The Journal of Chemical Physics (2016), 145(24), 241101Detailed reference viewed: 189 (3 UL) Materials perspective on Casimir and van der Waals interactionsWoods, L. M.; Dalvit, D. A. R.; Tkatchenko, Alexandre et alin Reviews of Modern Physics (2016), 88Detailed reference viewed: 158 (1 UL) Identical Binding Energies and Work Functions for Distinct Adsorption Structures: Olympicenes on the Cu(111) SurfaceLiu, Wei; Schuler, Bruno; Xu, Yong et alin The Journal of Physical Chemistry Letters (2016), 7(6), 1022-1027Detailed reference viewed: 190 (1 UL) Nature of Hydrogen Bonds and S···S Interactions in the l-Cystine CrystalFlores-Huerta, Anaid G.; Tkatchenko, Alexandre ; Galván, Marceloin The Journal of Physical Chemistry A (2016), 120(24), 4223-4230Detailed reference viewed: 164 (0 UL) Noncovalent Bonding Controls Selectivity in Heterogeneous Catalysis: Coupling Reactions on GoldKarakalos, Stavros; Xu, Yunfei; Cheenicode Kabeer, Fairoja et alin Journal of the American Chemical Society (2016), 138(46), 15243-15250Detailed reference viewed: 239 (0 UL) Reproducibility in density functional theory calculations of solidsLejaeghere, K.; Bihlmayer, G.; Tkatchenko, Alexandre et alin Science (2016), 351Detailed reference viewed: 422 (10 UL) Thermal and electronic fluctuations of flexible adsorbed molecules: Azobenzene on Ag(111)Maurer, Reinhard J.; Liu, Wei; Poltavskyi, Igor et alin Physical Review Letters (2016), 116Detailed reference viewed: 175 (4 UL) Density-functional theory with screened van der Waals interactions applied to atomic and molecular adsorbates on close-packed and non-close-packed surfacesRuiz, Victor G.; Liu, Wei; Tkatchenko, Alexandre in PHYSICAL REVIEW B (2016), 93(3), Modeling the adsorption of atoms and molecules on surfaces requires efficient electronic-structure methods that are able to capture both covalent and noncovalent interactions in a reliable manner. In ... [more ▼]Modeling the adsorption of atoms and molecules on surfaces requires efficient electronic-structure methods that are able to capture both covalent and noncovalent interactions in a reliable manner. In order to tackle this problem, we have developed a method within density-functional theory (DFT) to model screened van der Waals interactions (vdW) for atoms and molecules on surfaces (the so-called DFT+vdW(surf) method). The relatively high accuracy of the DFT+vdW(surf) method in the calculation of both adsorption distances and energies, as well as the high degree of its reliability across a wide range of adsorbates, indicates the importance of the collective electronic effects within the extended substrate for the calculation of the vdW energy tail. We examine in detail the theoretical background of the method and assess its performance for adsorption phenomena including the physisorption of Xe on selected close-packed transition metal surfaces and 3,4,9,10-perylene-tetracarboxylic acid dianhydride (PTCDA) on Au(111). We also address the performance of DFT+vdW(surf) in the case of non-close-packed surfaces by studying the adsorption of Xe on Cu(110) and the interfaces formed by the adsorption of a PTCDA monolayer on the Ag(111), Ag(100), and Ag(110) surfaces. We conclude by discussing outstanding challenges in the modeling of vdW interactions for studying atomic and molecular adsorbates on inorganic substrates. [less ▲]Detailed reference viewed: 179 (1 UL) Current Understanding of Van der Waals Effects in Realistic MaterialsTkatchenko, Alexandre in ADVANCED FUNCTIONAL MATERIALS (2015), 25(13, SI), 2054-2061Van der Waals (vdW) interactions arise from correlated electronic fluctuations in matter and are therefore present in all materials. Our understanding of these relatively weak yet ubiquitous quantum ... [more ▼]Van der Waals (vdW) interactions arise from correlated electronic fluctuations in matter and are therefore present in all materials. Our understanding of these relatively weak yet ubiquitous quantum mechanical interactions has improved significantly during the past decade. This understanding has been largely driven by the development of efficient methods that now enable the modeling of vdW interactions in many realistic materials of interest for fundamental scientific questions and technological applications. In this work, the physics behind the currently available vdW methods are reviewed, and their applications to a wide variety of materials are highlighted, ranging from molecular assemblies to solids with and without defects, nanostructures of varying size and dimensionality, as well as interfaces between inorganic and organic materials. The origin of collective vdW interactions in materials is discussed using the concept of topological dipole waves. Focus is placed on the important observation that the full many-body treatment of vdW interactions becomes crucial in the investigation and characterization of materials with increasing complexity, especially when studying their response properties, including vibrational mechanical, and optical phenomena. Despite significant recent advances many challenges still remain in the development of accurate and efficient methods for treating vdW interactions that will be broadly applicable to the modeling of functional materials at all relevant length and timescales. [less ▲]Detailed reference viewed: 173 (4 UL) Many-body dispersion effects in the binding of adsorbates on metal surfacesMaurer, Reinhard J.; Ruiz, Victor G.; Tkatchenko, Alexandre in JOURNAL OF CHEMICAL PHYSICS (2015), 143(10), A correct description of electronic exchange and correlation effects for molecules in contact with extended (metal) surfaces is a challenging task for first-principles modeling. In this work, we ... [more ▼]A correct description of electronic exchange and correlation effects for molecules in contact with extended (metal) surfaces is a challenging task for first-principles modeling. In this work, we demonstrate the importance of collective van der Waals dispersion effects beyond the pairwise approximation for organic-inorganic systems on the example of atoms, molecules, and nanostructures adsorbed on metals. We use the recently developed many-body dispersion (MBD) approach in the context of density-functional theory [Tkatchenko et al., Phys. Rev. Lett. 108 236402 (2012) and Ambrosetti et al., J. Chem. Phys. 140, 18A508 (2014)] and assess its ability to correctly describe the binding of adsorbates on metal surfaces. We briefly review the MBD method and highlight its similarities to quantum-chemical approaches to electron correlation in a quasiparticle picture. In particular, we study the binding properties of xenon, 3,4,9,10-perylene-tetracarboxylic acid, and a graphene sheet adsorbed on the Ag(111) surface. Accounting for MBD effects, we are able to describe changes in the anisotropic polarizability tensor, improve the description of adsorbate vibrations, and correctly capture the adsorbate-surface interaction screening. Comparison to other methods and experiment reveals that inclusion of MBD effects improves adsorption energies and geometries, by reducing the overbinding typically found in pairwise additive dispersion-correction approaches. (C) 2015 AIP Publishing LLC. [less ▲]Detailed reference viewed: 140 (5 UL) Electronic Properties of Molecules and Surfaces with a Self-Consistent Interatomic van der Waals Density FunctionalFerri, Nicola; DiStasio, Robert A. Jr; Ambrosetti, Alberto et alin PHYSICAL REVIEW LETTERS (2015), 114(17), How strong is the effect of van der Waals (vdW) interactions on the electronic properties of molecules and extended systems? To answer this question, we derived a fully self-consistent implementation of ... [more ▼]How strong is the effect of van der Waals (vdW) interactions on the electronic properties of molecules and extended systems? To answer this question, we derived a fully self-consistent implementation of the density-dependent interatomic vdW functional of Tkatchenko and Scheffler [Phys. Rev. Lett. 102, 073005 (2009)]. Not surprisingly, vdW self-consistency leads to tiny modifications of the structure stability, and electronic properties of molecular dimers and crystals. However, unexpectedly large effects were found in the binding energies distances, and electrostatic moments of highly polarizable alkali-metal dimers. Most importantly, vdW interactions induced complex and sizable electronic charge redistribution in the vicinity of metallic surfaces and at organic-metal interfaces. As a result, a substantial influence on the computed work functions was found, revealing a nontrivial connection between electrostatics and long-range electron correlation effects. [less ▲]Detailed reference viewed: 190 (3 UL) Steps or Terraces? Dynamics of Aromatic Hydrocarbons Adsorbed at Vicinal Metal SurfacesCamarillo-Cisneros, Javier; Liu, Wei; Tkatchenko, Alexandre in Physical Review Letters (2015), 115(8), The study of how molecules adsorb, diffuse, interact, and desorb from imperfect surfaces is essential for a complete understanding of elementary surface processes under relevant pressure and temperature ... [more ▼]The study of how molecules adsorb, diffuse, interact, and desorb from imperfect surfaces is essential for a complete understanding of elementary surface processes under relevant pressure and temperature conditions. Here we use first-principles calculations to study the adsorption of benzene and naphthalene on a vicinal Cu(443) surface with the aim to gain insight into the behavior of aromatic hydrocarbons on realistic surfaces at a finite temperature. Upon strong adsorption at step edges at a low temperature, the molecules then migrate from the step to the (111) terraces, where they can freely diffuse parallel to the step edge. This migration happens at temperatures well below the onset of desorption, suggesting a more complex dynamical picture than previously proposed from temperature-programed desorption studies. The increase of the adsorption strength observed in experiments for Cu(443) when compared to Cu(111) is explained by a stronger long-range van der Waals attraction between the hydrocarbons and the step edges of the Cu(443) surface. Our calculations highlight the need for time-resolved experimental studies to fully understand the dynamics of molecular layers on surfaces. © 2015 American Physical Society. [less ▲]Detailed reference viewed: 160 (2 UL) Machine learning predictions of molecular properties: Accurate many-body potentials and nonlocality in chemical spaceHansen, K.; Biegler, F.; Ramakrishnan, R. et alin Journal of Physical Chemistry Letters (2015), 6(12), 2326-2331Simultaneously accurate and efficient prediction of molecular properties throughout chemical compound space is a critical ingredient toward rational compound design in chemical and pharmaceutical ... [more ▼]Simultaneously accurate and efficient prediction of molecular properties throughout chemical compound space is a critical ingredient toward rational compound design in chemical and pharmaceutical industries. Aiming toward this goal, we develop and apply a systematic hierarchy of efficient empirical methods to estimate atomization and total energies of molecules. These methods range from a simple sum over atoms, to addition of bond energies, to pairwise interatomic force fields, reaching to the more sophisticated machine learning approaches that are capable of describing collective interactions between many atoms or bonds. In the case of equilibrium molecular geometries, even simple pairwise force fields demonstrate prediction accuracy comparable to benchmark energies calculated using density functional theory with hybrid exchange-correlation functionals; however, accounting for the collective many-body interactions proves to be essential for approaching the "holy grail" of chemical accuracy of 1 kcal/mol for both equilibrium and out-of-equilibrium geometries. This remarkable accuracy is achieved by a vectorized representation of molecules (so-called Bag of Bonds model) that exhibits strong nonlocality in chemical space. In addition, the same representation allows us to predict accurate electronic properties of molecules, such as their polarizability and molecular frontier orbital energies. © 2015 American Chemical Society. [less ▲]Detailed reference viewed: 237 (8 UL) van der Waals dispersion interactions in molecular materials: beyond pairwise additivityReilly, Anthony M.; Tkatchenko, Alexandre in Chemical Science (2015), 6(6), 3289-3301van der Waals (vdW) dispersion interactions are a key ingredient in the structure, stability, and response properties of many molecular materials and essential for us to be able to understand and design ... [more ▼]van der Waals (vdW) dispersion interactions are a key ingredient in the structure, stability, and response properties of many molecular materials and essential for us to be able to understand and design novel intricate molecular systems. Pairwise-additive models of vdW interactions are ubiquitous, but neglect their true quantum-mechanical many-body nature. In this perspective we focus on recent developments and applications of methods that can capture collective and many-body effects in vdW interactions. Highlighting a number of recent studies in this area, we demonstrate both the need for and usefulness of explicit many-body treatments for obtaining qualitative and quantitative accuracy for modelling molecular materials, with applications presented for small-molecule dimers, supramolecular host-guest complexes, and finally stability and polymorphism in molecular crystals. [less ▲]Detailed reference viewed: 170 (8 UL) Sliding Mechanisms in Multilayered Hexagonal Boron Nitride and Graphene: The Effects of Directionality, Thickness, and Sliding ConstraintsGao, Wang; Tkatchenko, Alexandre in PHYSICAL REVIEW LETTERS (2015), 114(9), The interlayer sliding potential of multilayered hexagonal boron nitride (h-BN) and graphene is investigated using density-functional theory including many-body van der Waals (vdW) interactions. We find ... [more ▼]The interlayer sliding potential of multilayered hexagonal boron nitride (h-BN) and graphene is investigated using density-functional theory including many-body van der Waals (vdW) interactions. We find that interlayer sliding constraints can be employed to tune the contribution of electrostatic interactions and dispersive forces to the sliding energy profile, ultimately leading to different sliding pathways in these two materials. In this context, vdW interactions are found to contribute more to the interlayer sliding potential of polar h-BN than they do in nonpolar graphene. In particular, the binding energy, the interlayer distance, and the friction force are found to depend sensitively on the number of layers. By comparing with the experimental findings, we identify sliding pathways which rationalize the observed reduced friction for thicker multilayers and provide quantitative explanation for the anisotropy of the friction force. [less ▲]Detailed reference viewed: 161 (4 UL) Quantitative Prediction of Molecular Adsorption: Structure and Binding of Benzene on Coinage MetalsLiu, Wei; Maass, Friedrich; Willenbockel, Martin et alin PHYSICAL REVIEW LETTERS (2015), 115(3), Interfaces between organic molecules and solid surfaces play a prominent role in heterogeneous catalysis, molecular sensors and switches light-emitting diodes, and photovoltaics. The properties and the ... [more ▼]Interfaces between organic molecules and solid surfaces play a prominent role in heterogeneous catalysis, molecular sensors and switches light-emitting diodes, and photovoltaics. The properties and the ensuing function of such hybrid interfaces often depend exponentially on molecular adsorption heights and binding strengths, calling for well-established benchmarks of these two quantities. Here we present systematic measurements that enable us to quantify the interaction of benzene with the Ag(111) coinage metal substrate with unprecedented accuracy (0.02 angstrom in the vertical adsorption height and 0.05 eV in the binding strength) by means of normal-incidence x-ray standing waves and temperature-programed desorption techniques. Based on these accurate experimental benchmarks for a prototypical molecule-solid interface, we demonstrate that recently developed first-principles calculations that explicitly account for the nonlocality of electronic exchange and correlation effects are able to determine the structure and stability of benzene on the Ag(111) surface within experimental error bars. Remarkably, such precise experiments and calculations demonstrate that despite different electronic properties of copper, silver, and gold, the binding strength of benzene is equal on the (111) surface of these three coinage metals. Our results suggest the existence of universal binding energy trends for aromatic molecules on surfaces. [less ▲]Detailed reference viewed: 163 (1 UL)