Latest in physics.chem-ph

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Embedded Atom Neural Network Potentials: Efficient and Accurate Machine Learning with a Physically Inspired RepresentationJul 14 2019We propose a simple, but efficient and accurate machine learning (ML) model for developing high-dimensional potential energy surface. This so-called embedded atom neural network (EANN) approach is inspired by the well-known empirical embedded atom method ... More
A New Approach For Learning Coarse-Grained Potentials with Application to Immiscible FluidsJul 13 2019Even though atomistic and coarse-grained (CG) models have been used to simulate liquid nanodroplets in vapor, very few rigorous studies of the liquid-liquid interface structure are available, and most of them are limited to planar interfaces. In this ... More
Cyano-functionalized Ag-bis-acetylide wires on Ag(110)Jul 13 2019Organometallic nanostructures are promising candidates for applications in optoelectronics, magnetism and catalysis. Our bottom-up approach employs a cyano-functionalized terminal alkyne species (CN-DETP) on the Ag(110) surface to fabricate 2D domains ... More
On the generalization of the exponential basis for tensor network representations of long-range interactions in two and three dimensionsJul 13 2019In one dimension (1D), a general decaying long-range interaction can be fit to a sum of exponential interactions $e^{-\lambda r_{ij}}$ with varying exponents $\lambda$, each of which can be represented by a simple matrix product operator (MPO) with bond ... More
Extending generalized Debye analysis to long timescale magnetic relaxationJul 12 2019As the ability to generate magnetic anisotropy in molecular materials continues to hit new milestones, concerted effort has shifted towards understanding, and potentially controlling, the mechanisms of magnetic relaxation across a large time and temperature ... More
The most stable isomer of H$_2$C$_4$-(OCS)$_2$ van der Waals complex: Theory and experiment agree on a structure with C2 symmetryJul 12 2019We report the infrared spectrum of H$_2$C$_4$-(OCS)$_2$ trimer in the region of the nu1 fundamental vibration of the OCS monomer. The van der Waals complexes are generated in a supersonic slit-jet apparatus and probed using a rapid-scan tunable diode ... More
Efficient global structure optimization with a machine learned surrogate modelJul 12 2019We propose a scheme for global optimization with first-principles energy expressions (GOFEE) of atomistic structure. While unfolding its search, the method actively learns a surrogate model of the potential energy landscape on which it performs a number ... More
Phase-field modeling of crystal nucleation in undercooled liquids -- A reviewJul 12 2019We review how phase-field models contributed to the understanding of various aspects of crystal nucleation including homogeneous and heterogeneous processes, and their role in microstructure evolution. We recall results obtained both by the conventional ... More
Theorie der Electrophorese -- Het Relaxatie-EffectJul 12 2019In this thesis, a theoretical treatment of the relation between electrophoretic velocity and the potential of the double layer of colloidal particles is presented. Translators' note: The theory of electrophoresis is one of the foundational topics that ... More
Sub-femtosecond tracing of molecular dynamics during strong-field interactionJul 11 2019We introduce and experimentally demonstrate a method, where the two intrinsic time scales of a molecule, the slow nuclear motion and the fast electronic motion, are simultaneously measured in a photo-electron photo-ion coincidence experiment. In our experiment, ... More
Nonrigidity effects -- a missing puzzle piece in the description of low-energy anisotropic molecular collisionsJul 11 2019Cold collisions serve as a very sensitive probe of the interaction potential. In the recent study of Klein et al. (Nature Phys. 13, 35-38 (2017)) the one-parameter scaling of the interaction potential was necessary to obtain agreement between theoretical ... More
Improving the Cauchy-Schwarz inequalityJul 11 2019We highlight overlap as one of the simplest inequalities in linear space that yields a number of useful results. One obtains the Cauchy-Schwarz inequality as a special case. More importantly, a variant of it is seen to work desirably in certain singular ... More
Partition of Optical Properties Into Orbital ContributionsJul 10 2019Nonlinear optical properties (NLOPs) play a major role in photonics, electro-optics and optoelectronics, and other fields of modern optics. The design of new NLO molecules and materials has benefited from the development of computational tools to analyze ... More
Eppur si riscalda -- and yet, it (just) heats up: Further Comments on "Quantifying hot carrier and thermal contributions in plasmonic photocatalysis"Jul 10 2019Our Comment [Sivan et al., Science 2019] (as well as its longer version [Dubi, Un, & Sivan, ArXiv 2019], and the supporting theoretical studies [Dubi and Sivan, ArXiv 2018]) on recent attempts to distinguish thermal and non-thermal ("hot carrier") contributions ... More
Lattice Boltzmann Electrokinetics simulation of nanocapacitorsJul 10 2019We propose a method to model metallic surfaces in Lattice Boltzmann Electrokinetics simulations (LBE), a lattice-based algorithm rooted in kinetic theory which captures the coupled solvent and ion dynamics in electrolyte solutions. This is achieved by ... More
Excited-State Nanophotonic and Polaritonic Chemistry with Ab initio Potential-Energy SurfacesJul 10 2019Advances in nanophotonics, quantum optics, and low-dimensional materials have enabled precise control of light-matter interactions down to the nanoscale. Combining concepts from each of these fields, there is now an opportunity to create and manipulate ... More
Cascaded Förster Resonance Energy Transfer and Role of the Relay DyeJul 10 2019The effect of introducing a relay dye on the energy transfer efficiency in a new donor-acceptor system has been studied. The values of the critical transfer distance, the reduced concentration, and the energy transfer efficiency of the cascaded system ... More
Interplay between Structural Hierarchy and Exciton Diffusion in Artificial Light HarvestingJul 10 2019Unravelling the nature of energy transport in multi-chromophoric photosynthetic complexes is essential to extract valuable design blueprints for light-harvesting applications. Long-range exciton transport in such systems is facilitated by a combination ... More
Approximating Free Energy and Committor Landscapes in Standard Transition Path Sampling using Virtual Interface ExchangeJul 09 2019Transition path sampling (TPS) is a powerful technique for investigating rare transitions, especially when the mechanism is unknown and one does not have access to the reaction coordinate. Straightforward application of TPS does not directly provide the ... More
Dendrite suppression of metal electrodeposition with liquid crystalline electrolytesJul 09 2019We study the dynamics of electrodeposition of a metal in contact with a liquid crystalline electrolyte. A nematic liquid crystalline electrolyte introduces an additional overpotential due to its bulk distortion and anchoring free energy. A phase-field ... More
A new scheme for fixed node diffusion quantum Monte Carlo with pseudopotentials: improving reproducibility and reducing the trial-wave-function biasJul 09 2019Fixed node diffusion quantum Monte Carlo (FN-DMC) is an increasingly used computational approach for investigating the electronic structure of molecules, solids, and surfaces with controllable accuracy. It stands out among equally accurate electronic ... More
Nonlinear Electrophoresis of Highly Charged Nonpolarizable ParticlesJul 09 2019Nonlinear field dependence of electrophoresis in high fields has been investigated theoretically, yet experimental studies have failed to reach consensus on the effect. In this work, we present a systematic study on the nonlinear electrophoresis of highly ... More
Singling Out Dynamic and Nondynamic CorrelationJul 09 2019The correlation part of the pair density is separated into two components, one of them being predominant at short electronic ranges and the other at long ranges. The analysis of the intracular part of these components permits to classify molecular systems ... More
Long-lived nuclear coherences inside helium nanodropletsJul 09 2019Much of our knowledge about dynamics and functionality of molecular systems has been achieved with femtosecond time-resolved spectroscopy. Despite extensive technical developments over the past decades, some classes of systems have eluded dynamical studies ... More
Deflation reveals dynamical structure in nondominant reaction coordinatesJul 09 2019The output of molecular dynamics simulations is high-dimensional, and the degrees of freedom among the atoms are related in intricate ways. Therefore, a variety of analysis frameworks have been introduced in order to distill complex motions into lower-dimensional ... More
Resolution limit of data-driven coarse-grained models spanning chemical spaceJul 09 2019Increasing the efficiency of materials design and discovery remains a significant challenge, especially given the prohibitively large size of chemical compound space. The use of a chemically transferable coarse-grained model enables different molecular ... More
Numerical modeling of chaotic bottom-up synthesis for alloy, Janus and core-shell nanoparticlesJul 09 2019While alloy, core-shell and Janus binary nanoclusters are found in more and more technological applications, their formation mechanisms are still poorly understood, especially during chaotic bottom-up synthesis. We study the nucleation and growth mechanisms ... More
Simulations of Crystal Nucleation from Solution at Constant Chemical PotentialJul 09 2019A widely spread method of crystal preparation is to precipitate it from a supersaturated solution. In such a process, control of solution concentration is of paramount importance. Nucleation process, polymorph selection, and crystal habits depend crucially ... More
Extending Single Molecule Förster Resonance Energy Transfer (FRET) Range Beyond 10 Nanometers in Zero-Mode WaveguidesJul 08 2019Single molecule F\"orster resonance energy transfer (smFRET) is widely used to monitor conformations and interactions dynamics at the molecular level. However, conventional smFRET measurements are ineffective at donor-acceptor distances exceeding 10 nm, ... More
$β$-detected NMR of $^8$Li$^+$ in 1-ethyl-3-methylimidazolium acetateJul 08 2019We report $\beta$-detected NMR ($\beta$-NMR) spin-lattice relaxation and resonance measurements of $^8$Li$^+$ implanted in 1-ethyl-3-methylimidazolium acetate, an ionic liquid. The motional narrowing of the resonance line, and the local maxima in the ... More
Noncovalent Interactions of Hydrated DNA and RNA Mapped by 2D-IR SpectroscopyJul 08 2019Biomolecules couple to their aqueous environment through a variety of noncovalent interactions. Local structures at the surface of DNA and RNA are frequently determined by hydrogen bonds with water molecules, complemented by non-specific electrostatic ... More
Control and imaging of molecular quantum states with second-scale coherenceJul 08 2019Cold molecules provide a platform for a variety of scientific applications such as quantum computation, simulation, cold chemistry, and searches for physics beyond the Standard Model. Mastering quantum state control and measurement of diverse molecular ... More
Measurement Optimization in the Variational Quantum Eigensolver Using a Minimum Clique CoverJul 07 2019Solving the electronic structure problem using the Variational Quantum Eigensolver (VQE) technique involves measurement of the Hamiltonian expectation value. Current hardware can perform only projective single-qubit measurements, and thus, the Hamiltonian ... More
Measurement Optimization in the Variational Quantum Eigensolver Using a Minimum Clique CoverJul 07 2019Jul 09 2019Solving the electronic structure problem using the Variational Quantum Eigensolver (VQE) technique involves measurement of the Hamiltonian expectation value. Current hardware can perform only projective single-qubit measurements, and thus, the Hamiltonian ... More
Tilting and Squeezing: Phase space geometry of Hamiltonian saddle-node bifurcation and its influence on chemical reaction dynamicsJul 07 2019In this article we present the influence of a Hamiltonian saddle-node bifurcation on the high-dimensional phase space structures that mediate reaction dynamics. To achieve this goal, we identify the phase space invariant manifolds using Lagrangian descriptors, ... More
Ionic Transport in Potential Coating Materials for Mg BatteriesJul 07 2019A major bottleneck for the development of Mg batteries is the identification of liquid electrolytes that are simultaneously compatible with the Mg-metal anode and high-voltage cathodes. One strategy to widen the stability windows of current non-aqueous ... More
MARVEL analysis of the measured high-resolution spectra of $^{14}$NHJul 07 2019Rovibronic energy levels are determined for four low-lying electronic states (\X, \A, \Sa, and \Sc) of the imidogen free radical ($^{14}$NH) using the \Marvel\ (Measured Active Rotational-Vibrational Energy Levels) technique. Compilation of transitions ... More
Structure determination of the tetracene dimer in helium nanodroplets using femtosecond strong-field ionizationJul 06 2019Dimers of tetracene molecules are formed inside helium nanodroplets and identified through covariance analysis of the emission directions of kinetic tetracene cations stemming from femtosecond laser-induced Coulomb explosion. Next, the dimers are aligned ... More
Encapsulation of oils and fragrances by core-in-shell structures from silica particles, polymers and surfactants: The brick-and-mortar conceptJul 06 2019Colloidosomes provide a possibility to encapsulate oily substances in water in the form of core-in-shell structures. In this study, we produced microcapsules with shell from colloidal particles, where the interparticle openings are blocked by mixed layers ... More
Path-integral dynamics of water using curvilinear centroidsJul 06 2019We develop a path-integral dynamics method for water that resembles centroid molecular dynamics (CMD), except that the centroids are averages of curvilinear, rather than cartesian, bead coordinates. The curvilinear coordinates are used explicitly only ... More
Analysis of Superfast Encoding Performance for Electronic Structure SimulationsJul 05 2019In our recent work, we have examined various fermion to qubit mappings in the context of quantum simulation including the original Bravyi-Kitaev Superfast encoding (OSE) as well as a generalized version (GSE). We return to OSE and compare it against the ... More
Control defeseance by anti-alignment in the excited stateJul 05 2019We predict anti-alignment dynamics in the excited state of H2+ or related homonuclear dimers in the presence of a strong field. This effect is a general indirect outcome of the strong transition dipole and large polarizabilities typically used to control ... More
Understanding Phonon Properties in Isoreticular Metal-Organic Frameworks from First PrinciplesJul 04 2019Metal-organic frameworks (MOFs) are crystalline materials consisting of metal centers and organic linkers forming open and porous structures. They have been extensively studied due to various possible applications exploiting their large amount of internal ... More
Continuous and Optimally Complete Description of Chemical Environments Using Spherical Bessel DescriptorsJul 04 2019Recently, machine learning potentials have been advanced as candidates to combine the high-accuracy of quantum mechanical simulations with the speed of classical interatomic potentials. A crucial component of a machine learning potential is the description ... More
A Novel Approach to Describe Chemical Environments in High Dimensional Neural Network PotentialsJul 04 2019A central concern of molecular dynamics simulations are the potential energy surfaces that govern atomic interactions. These hypersurfaces define the potential energy of the system, and have generally been calculated using either predefined analytical ... More
Electronic structure of 3$d$-transition-metal monoxide anions from $GW$ calculations: ScO$^{-}$, TiO$^{-}$, CuO$^{-}$, and ZnO$^{-}$Jul 04 2019The $GW$ approximation to many-body perturbation theory is a reliable tool for describing charged electronic excitations, and it has been successfully applied to a wide range of extended systems for several decades using a plane-wave basis. However, the ... More
A Nonequilibrium Variational Polaron Theory to Study Quantum Heat TransportJul 03 2019We propose a nonequilibrium variational polaron transformation, based on an ansatz for nonequilibrium steady state (NESS) with an effective temperature, to study quantum heat transport at the nanoscale. By combining the variational polaron transformed ... More
Enhanced Delayed Fluorescence in Tetracene Crystals by Strong Light-Matter CouplingJul 03 2019We demonstrate experimentally an enhanced delayed fluorescence in tetracene single crystals strongly coupled to optical modes in open cavities formed by arrays of plasmonic nanoparticles. Hybridization of singlet excitons with collective plasmonic resonances ... More
Effect of Oxygen Defects Blocking Barriers on Gadolinium Doped Ceria (GDC) Electro-Chemo-Mechanical PropertiesJul 03 2019Some oxygen defective metal oxides, such as cerium and bismuth oxides, have recently shown exceptional electrostrictive properties that are even superior to the best performing lead-based electrostrictors, e.g. lead-magnesium-niobates (PMN). Compared ... More
Large presence of carbonic acid in CO$_2$-rich aqueous fluids under Earth's mantle conditionsJul 03 2019The chemistry of carbon in aqueous fluids at extreme pressure and temperature conditions is of great importance to Earth's deep carbon cycle, which substantially affects the carbon budget at Earth's surface and global climate change. At ambient conditions, ... More
Generative Models for Automatic Chemical DesignJul 02 2019Materials discovery is decisive for tackling urgent challenges related to energy, the environment, health care and many others. In chemistry, conventional methodologies for innovation usually rely on expensive and incremental strategies to optimize properties ... More
Predicting Retrosynthetic Reaction using Self-Corrected Transformer Neural NetworksJul 02 2019Jul 03 2019Synthesis planning is the process of recursively decomposing target molecules into available precursors. Computer-aided retrosynthesis can potentially assist chemists in designing synthetic routes, but at present it is cumbersome and provides results ... More
Chemically Accurate Excitation Energies With Small Basis SetsJul 02 2019By combining extrapolated selected configuration interaction (sCI) energies obtained with the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) algorithm with the recently proposed short-range density-functional correction ... More
Chemically Accurate Excitation Energies With Small Basis SetsJul 02 2019Jul 03 2019By combining extrapolated selected configuration interaction (sCI) energies obtained with the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) algorithm with the recently proposed short-range density-functional correction ... More
A Demonstration of Consistency between the Quantum Classical Liouville Equation and Berry's Phase and CurvatureJul 01 2019Although the quantum classical Liouville equation (QCLE) arises by cutting off the exact equation of motion for a coupled nuclear-electronic system at order 1 (1 = $\hbar^0$ ), we show that the QCLE does include Berry's phase effects and Berry's forces ... More
Local-in-time error in variational quantum dynamicsJul 01 2019The McLachlan "minimum-distance" principle for optimizing approximate solutions of the time-dependent Schrodinger equation is revisited, with a focus on the local-in-time error accompanying the variational solutions. Simple, exact expressions are provided ... More
Semiclassical vibrational spectroscopy with Hessian databasesJul 01 2019We report on a new approach to ease the computational overhead of ab initio on-the-fly semiclassical dynamics simulations for vibrational spectroscopy. The well known bottleneck of such computations lies in the necessity to estimate the Hessian matrix ... More
Automatic Routing of Goldstone Diagrams using Genetic AlgorithmsJun 30 2019This paper presents an algorithm for an automatic transformation (=routing) of time ordered topologies of Goldstone diagrams (i.e. Wick contractions) into graphical representations of these topologies. Since there is no hard criterion for an optimal routing, ... More
Semiclassical dynamics in the mixed quantum-classical limitJun 29 2019The semiclassical Double Herman-Kluk Initial Value Representation is an accurate approach to computing quantum real time correlation functions, but its applications are limited by the need to evaluate an oscillatory integral. In previous work, we have ... More
System size dependence of hydration shell occupancyJun 29 2019Jul 03 2019The free energies to evacuate the first hydration shell around a solute and a cavity defined by the first hydration shell depend on the system size. This observation interpreted within the quasichemical theory shows that both the hydrophilic and the hydrophobic ... More
Exact exchange-correlation potential of effectively interacting Kohn-Sham systemsJun 29 2019Aiming to combine density functional theory (DFT) and wavefunction theory, we study a mapping from the many-body interacting system to an effectively-interacting Kohn-Sham system instead of a non-interacting Kohn-Sham system. Because a ground state of ... More
Long-range vs. short-range effects in cold molecular ion-neutral collisions: Charge exchange of Rb with N$_2^+$ and O$_2^+$Jun 28 2019We report a study of cold charge-transfer (CT) collisions of Rb atoms with N$_2^+$ and O$_2^+$ ions in the mK regime using a dynamic ion-neutral hybrid trapping experiment. State- and collision-energy- dependent reaction rate coefficients have been measured ... More
Far-from-equilibrium dynamics of angular momentum in a quantum many-particle systemJun 28 2019We use laser-induced rotation of single molecules embedded in superfluid helium nanodroplets to reveal angular momentum dynamics and transfer in a controlled setting, under far-from-equilibrium conditions. As an unexpected result, we observe pronounced ... More
Far-from-equilibrium dynamics of angular momentum in a quantum many-particle systemJun 28 2019Jul 08 2019We use laser-induced rotation of single molecules embedded in superfluid helium nanodroplets to reveal angular momentum dynamics and transfer in a controlled setting, under far-from-equilibrium conditions. As an unexpected result, we observe pronounced ... More
Temperature-Dependent Lifetimes of Low-Frequency Adsorbate Modes from Non-Equilibrium Molecular Dynamics SimulationsJun 27 2019We present calculations on the damping of a low-frequency adsorbate mode on a metal surface, namely the frustrated translation of Na on Cu(100). For the first time, vibrational lifetimes of excited adlayers are extracted from non-equilibrium molecular ... More
The covalent radii derived from the first-principle dataJun 27 2019We present a collection of covalent radii for the elements H, B, C, N, O, F, Si, P, S, Cl, Ge, As, Se, Br, derived from the recently introduced systematic non-empirical dataset of the covalent bond lengths. As the underlying bond lengths dataset was built ... More
Collisional excitation of NH(3Σ-) by Ar: A new ab initio 3D potential energy surface and scattering calculationsJun 27 2019Collisional excitation of light hydrides is important to fully understand the complex chemical and physical processes of atmospheric and astrophysical environments. Here, we focus on the NH(X3{\Sigma}-)-Ar van der Waals system. First, we have calculated ... More
Deep neural network for Wannier function centersJun 27 2019We introduce a deep neural network (DNN) model that assigns the position of the centers of the electronic charge in each atomic configuration on a molecular dynamics trajectory. The electronic centers are uniquely specified by the unitary transformation ... More
Deep neural network for Wannier function centersJun 27 2019Jul 02 2019We introduce a deep neural network (DNN) model that assigns the position of the centers of the electronic charge in the snapshots of a molecular dynamics trajectory. The electronic centers are uniquely specified by the unitary transformation that maps ... More
Feshbach projection XMCQDPT2 model for metastable electronic statesJun 26 2019Autoionizing electronic states are common intermediates in processes initiated by electron impact or high-energy radiation. These states belong to the continuous spectrum of the Hamiltonian, and as such cannot be treated with methods developed for bound ... More
Chemistry on Rotating Grain Surface: Ro-Thermal Desorption of Molecules from Ice MantlesJun 26 2019It is widely believed that water and complex organic molecules (COMs) first form in the ice mantle of dust grains and are subsequently returned into the gas due to grain heating by intense radiation of protostars. Previous research on the desorption of ... More
Geminal-Based Configuration InteractionJun 26 2019The antisymmetrized geminal power (AGP) wave function has a long history and considerable conceptual appeal, but in many situations its accuracy is wanting. Here, we consider a form of configuration interaction (CI) based upon the AGP wave function and ... More
Non-Adiabatic Molecular Dynamics of Molecules in the Presence of Strong Light-Matter InteractionsJun 26 2019When confined photonic modes in an optical or plasmonic cavity interact strongly with a molecule, new hybrid light-matter states, termed as polaritonic states, can form. The newly formed polaritonic states are the superpositions of electrons (excitons) ... More
Iterative qubit coupled cluster method: A systematic approach to the full-CI limit in quantum chemistry calculations on NISQ devicesJun 26 2019Noisy intermediate-scale quantum (NISQ) devices is the current realm of quantum computing. To exploit their limited powers to full extent it is imperative to develop suitable algorithms. We present the iterative qubit coupled cluster (iQCC) method aimed ... More
Near 100% CO Selectivity in Nanoscaled Iron-Based Oxygen Carriers for Chemical Looping Methane Partial OxidationJun 26 2019Chemical looping methane partial oxidation provides an energy and cost effective route for methane utilization. However, there is considerable CO2 co-production in state-of-the-art chemical looping systems, rendering a decreased productivity in value-added ... More
Chemically reversible isomerization of inorganic clustersJun 26 2019Structural transformations in molecules and solids have generally been studied in isolation, while intermediate systems have eluded characterization. We show that a pair of CdS cluster isomers provides an advantageous experimental platform to study isomerization ... More
Direct Quantification of Water Surface Charge by Phase-Sensitive Second Harmonic SpectroscopyJun 26 2019Electrical double layer (EDL) at water interfaces is an essential ingredient for diverse biological and chemical processes, yet to characterize the EDL quantitatively in atmosphere without model assumption remains a challenge. Based on optical second ... More
Unconventional phase III of high-pressure solid hydrogenJun 26 2019We reassess the phase diagram of high-pressure solid hydrogen using mean-filed and many-body wave function based approaches to determine the nature of phase III of solid hydrogen. To discover the best candidates for the phase III, Density Functional Theory ... More
Real-time probing of chirality during a chemical reactionJun 26 2019Chiral molecules interact and react differently with other chiral objects, depending on their handedness. Therefore, it is essential to understand and ultimately control the evolution of molecular chirality during chemical reactions. Although highly sophisticated ... More
Computational Investigations of the Lithium Superoxide Dimer Rearrangement on Noisy Quantum DevicesJun 25 2019Currently available noisy intermediate-scale quantum (NISQ) devices are limited by the number of qubits that can be used for quantum chemistry calculations on molecules. We show herein that the number of qubits required for simulations on a quantum computer ... More
Phase Transition Pathway Sampling via Swarm Intelligence and Graph TheoryJun 25 2019The prediction of reaction pathways for solid-solid transformations remains a key challenge. Here, we develop a pathway sampling method via swarm intelligence and graph theory, and demonstrate that our PALLAS method is an effective tool to help understand ... More
Energy Landscapes for Digital AlchemyJun 25 2019We apply energy landscape methods to digital alchemy, defining a system in which the parameters of the potential are treated as degrees of freedom. Using geometrical optimisation, we locate minima and transition states on the landscape for small clusters. ... More
Advances and challenges in single-molecule electron transportJun 25 2019Electronic transport properties for single-molecule junctions have been widely measured by several techniques, including mechanically controllable break junctions, electromigration break junctions or by means of scanning tunneling microscopes. In parallel, ... More
Laser-Induced Dissociative Recombination of Carbon DioxideJun 25 2019We experimentally investigate laser-induced dissociative recombination of CO$_2$ in linearly polarized strong laser fields with coincidence measurements. Our results show laser-induced dissociation processes originate from an electron recombination process ... More
Full Wave Function Optimization with Quantum Monte Carlo -- A study of the Dissociation Energies of ZnO, FeO, FeH, and CrSJun 25 2019The dissociation energies of four transition metal dimers are determined by means of diffusion Monte Carlo. The Jastrow, CI, and molecular orbital parameters of the wave function are both partially and fully optimized with respect to the variational energy. ... More
Scaled and Dynamic Optimizations of Nudged Elastic BandsJun 24 2019We present a modified nudged elastic band routine that can reduce the number of force calls by more than 50% for bands with non-uniform convergence. The method, which we call "dyNEB", dynamically and selectively optimizes states based on the perpendicular ... More
The Exploration of Chemical Reaction NetworksJun 24 2019Modern computational chemistry has reached a stage at which massive exploration into chemical reaction space with unprecedented resolution with respect to the number of potentially relevant molecular structures has become possible. Various algorithmic ... More
Unifying machine learning and quantum chemistry -- a deep neural network for molecular wavefunctionsJun 24 2019Machine learning advances chemistry and materials science by enabling large-scale exploration of chemical space based on quantum chemical calculations. While these models supply fast and accurate predictions of atomistic chemical properties, they do not ... More
Mn-Intercalated MoSe$_2$ under pressure: electronic structure and vibrational characterization of a dilute magnetic semiconductorJun 24 2019Intercalation offers a promising way to alter the physical properties of two-dimensional (2D) layered materials. Here, Raman scattering of 2D layered MoSe$_2$ intercalated with atomic manganese is investigated at ambient and high pressure up to 7 GPa. ... More
Phonon Mediated Multiquantum Vibrational Relaxation of NO Scattered from Au(111)Jun 24 2019Multi-quantum relaxation of highly vibrationally excited NO scattering from Au(111) represents a benchmark demonstration of the breakdown of Born-Oppenheimer approximation in molecule-surface systems. This remarkable vibrational inelasticity was long ... More
Ultracold Collisions of Polyatomic Molecules: CaOHJun 23 2019Ultracold collisions of the polyatomic species CaOH are considered, in internal states where the collisions should be dominated by long-range dipole-dipole interactions. The computed rate constants suggest that evaporative cooling can be quite efficient ... More
Discovery of the first Ca-bearing molecule in space: CaNCJun 21 2019We report on the detection of calcium isocyanide, CaNC, in the carbon-rich evolved star IRC+10216. We derived a column density for this species of (2.0$\pm$0.5)$\times$10$^{11}$ cm$^{-2}$. Based on the observed line profiles and the modelling of its emission ... More
Gaussian Process-Based Refinement of Dispersion CorrectionsJun 21 2019We employ Gaussian process (GP) regression to adjust for systematic errors in D3-type dispersion corrections introducing the associated, statistically improved model D3-GP. We generated a data set containing interaction energies for 1,248 molecular dimers, ... More
Depletion force between disordered linear macromoleculesJun 21 2019When two macromolecules come very near in a fluid, the molecules that surround them, having finite volume, are less likely to get in between. This leads to a pressure difference manifesting as an entropic attraction, called depletion force. Here we calculate ... More
On the Properties of Monocyclic Systems, and others related to themJun 21 2019Translation of Ludwig Boltzmann's paper "\"Uber die Eigenschaften monozyklischer und anderer damit verwandter Systeme" Crelles Journal 98. S. 68-94. 1884 u. 1885 from German into English. In this foundational paper Boltzmann introduced two key concepts ... More
Modeling discontinuous potential distributions using the finite volume method, and application to liquid metal batteriesJun 21 2019The electrical potential in a battery jumps at each electrode-electrolyte interface. We present a model for computing three-dimensional current and potential distributions, which accounts for such internal voltage jumps. Within the framework of the finite ... More
Direct observation of water mediated single proton transport between hBN surface defectsJun 21 2019Aqueous proton transport at interfaces is ubiquitous and crucial for a number of fields, ranging from cellular transport and signaling, to catalysis and membrane science. However, due to their light mass, small size and high chemical reactivity, uncovering ... More
Fluctuating exchange interactions enable quintet multiexciton formation in singlet fissionJun 21 2019Jun 27 2019Several recent electron spin resonance studies have observed a quintet multiexciton state during the singlet fission process. Here we provide a general theoretical explanation for the generation of this state by invoking a time-varying exchange coupling ... More
Fluctuating exchange interactions enable quintet multiexciton formation in singlet fissionJun 21 2019Several recent electron spin resonance studies have observed a quintet multiexciton state during the singlet fission process. Here we provide a general theoretical explanation for the generation of this state by invoking a time-varying exchange coupling ... More
Hiding in the crowd: Spectral signatures of overcoordinated hydrogen bond environmentsJun 21 2019Molecules with an excess number of hydrogen-bonding partners play a crucial role in fundamental chemical processes, ranging from the anomalous diffusion in supercooled water to the transport of aqueous proton defects and the ordering of water around hydrophobic ... More