English
Related papers

Related papers: Hydrogen dissociation on the Mg(0001) surface from…

200 papers

Many chemical reactions involve bond-dissociation. This is also true for reactions at solid surfaces, in which the dissociation step is often limiting but facilitated in comparison to gas phase reaction channels. This work considers…

Materials Science · Physics 2015-11-25 Philip E Hoggan

We present quantum Monte Carlo calculations for various reaction pathways of H$_2$ with Si(001), using large model clusters of the surface. We obtain reaction energies and energy barriers noticeably higher than those from approximate…

Materials Science · Physics 2009-11-07 Claudia Filippi , Sorcha B. Healy , P. Kratzer , E. Pehlke , M. Scheffler

Diffusion Monte Carlo (DMC) is being recognized as a higher-accuracy, albeit more computationally expensive, alternative to Density Functional Theory (DFT) for energy predictions of catalytic systems. A major computational bottleneck in the…

Materials Science · Physics 2022-10-12 Gopal R. Iyer , Brenda M. Rubenstein

Fixed node diffusion Monte Carlo (DMC) has been performed on a test set of forward and reverse barrier heights for 19 non-hydrogen-transfer reactions, and the nodal error has been assessed. The DMC results are robust to changes in the nodal…

Chemical Physics · Physics 2017-04-26 Kittithat Krongchon , Brian Busemeyer , Lucas K. Wagner

Using first-principles calculations, we systematically study the potential energy surfaces and dissociation processes for hydrogen molecules on the clean and hydrogen-preadsorbed Be(0001) surfaces. It is found that the most energetically…

Materials Science · Physics 2015-05-13 Yanfang Li , Yu Yang , Bo Sun , Yinghui Wei , Ping Zhang

Density functional theory (DFT) is widely used in surface science, but gives poor accuracy for oxide surface processes, while high-level quantum chemistry methods are hard to apply without losing basis-set quality. We argue that quantum…

Materials Science · Physics 2007-05-23 D. Alfe` , M. J. Gillan

We report a study of the electronic dissociation energy of the water dimer using quantum Monte Carlo (QMC) techniques. We have performed variational quantum Monte Carlo (VMC) and diffusion quantum Monte Carlo (DMC) calculations of the…

Other Condensed Matter · Physics 2009-11-13 I. G. Gurtubay , R. J. Needs

The yardstick of new first-principles approaches to key points on reaction paths at metal surfaces is chemical accuracy compared to reliable experiment. By this we mean that such values as the activation barrier are required to within 1…

Materials Science · Physics 2017-05-24 Philip E Hoggan

It is well known, both theoretically and experimentally, that alloying MgH$_2$ with transition elements can significantly improve the thermodynamic and kinetic properties for H$_2$ desorption, as well as the H$_2$ intake by Mg bulk. Here we…

Materials Science · Physics 2009-11-13 M. Pozzo , D. Alfè , A. Amieiro , S. French , A. Pratt

The kinetics of hydrogen absorption by magnesium bulk is affected by two main activated processes: the dissociation of the H$_2$ molecule and the diffusion of atomic H into the bulk. In order to have fast absorption kinetics both activated…

Materials Science · Physics 2008-11-17 Monica Pozzo , Dario Alfe`

We have used diffusion Monte Carlo (DMC) calculations to study the structural properties of magnesium hydride (MgH$_2$), including the pressure-volume equation of state, the cohesive energy and the enthalpy of formation from magnesium bulk…

Materials Science · Physics 2009-11-13 M. Pozzo , D. Alfè

We report diffusion Monte Carlo (DMC) calculations on MgO in the rock-salt and CsCl structures. The calculations are based on Hartree-Fock pseudopotentials, with the single-particle orbitals entering the correlated wave function being…

Strongly Correlated Electrons · Physics 2016-08-16 D. Alfè , M. Alfredsson , J. Brodholt , M. J. Gillan M. D. Towler , R. J. Needs

In this paper the Diffusion Monte Carlo (DMC) method is applied to the confined hydrogen atom with different confinement geometries. This approach is validated using the much studied spherical and cylindrical confinements and then applied…

Chemical Physics · Physics 2019-03-20 Gaia Micca Longo , Savino Longo , Domenico Giordano

The many-body diffusion quantum Monte Carlo (DMC) method with twist-averaged boundary conditions is used to calculate the ground-state equation of state and the energetics of point defects in fcc aluminum using supercells up to 1331 atoms.…

Materials Science · Physics 2012-10-22 Randolph Q. Hood , P. R. C. Kent , Fernando A. Reboredo

The yardstick of new first-principles approaches to key points on reaction paths at metal surfaces is chemical accuracy compared to reliable experiment. By this we mean that such values as the activation barrier are required to within 1…

Chemical Physics · Physics 2018-06-14 Philip E. Hoggan

We use the diffusion quantum Monte Carlo (DMC) method to calculate the ground state phase diagram of solid molecular hydrogen and examine the stability of the most important insulating phases relative to metallic crystalline molecular…

Materials Science · Physics 2015-06-16 S. Azadi , W. M. C. Foulkes , T. D. Kuehne

The Diffusion Monte Carlo (DMC) method is applied to compute the ground state energies of the water monomer and dimer and their D 2 O isotopomers using MB-pol; the most recent and most accurate ab inito- based potential energy surface…

Chemical Physics · Physics 2015-10-28 Joel Mallory , Vladimir Mandelshtam

We present a quantum Monte Carlo study of the hydrogen-benzene system where binding is very weak. We demonstrate that the binding is well described at both variational Monte Carlo (VMC) and diffusion Monte Carlo (DMC) levels by a Jastrow…

Materials Science · Physics 2009-11-13 Todd D. Beaudet , Michele Casula , Jeongnim Kim , Sandro Sorella , Richard M. Martin

The dissociation of a hydrogen molecule on MgO(001) films deposited on Mo(001) surface is investigated systematically using periodic density-functional theory method. The unusual adsorption behavior of heterolytic dissociative hydrogen…

Chemical Physics · Physics 2016-04-29 Zhenjun Song , Hu Xu

By Using the variational Monte Carlo (VMC) method, we calculate the 1s{\sigma}_g state energies, the dissociation energies and the binding energies of the hydrogen molecule and its molecular ion in the presence of an aligned magnetic field…

Atomic Physics · Physics 2016-06-29 S. B. Doma , M. Abu-Shady , F. N. El-Gamma , A. A. Amer
‹ Prev 1 2 3 10 Next ›