269 citations · 1.1k across the 15 of their papers we have counts for
15 papers
Energy benchmarks for water clusters and ice structures from an embedded many-body expansion
M. J. Gillan, D. Alfe, P. J. Bygrave +2
We show how an embedded many-body expansion (EMBE) can be used to calculate accurate \emph{ab initio} energies of water clusters and ice structures using wavefunction-based methods…
Assessing the accuracy of quantum Monte Carlo and density functional theory for energetics of small water clusters
M. J. Gillan, F. R. Manby, M. D. Towler +1
We present a detailed study of the energetics of water clusters (HO) with , comparing diffusion Monte Carlo (DMC) and approximate density functional theory (DFT) w…
Ab initio statistical mechanics of surface adsorption and desorption: II. Nuclear quantum effects
D. Alfe`, M. J. Gillan
We show how the path-integral formulation of quantum statistical mechanics can be used to construct practical {\em ab initio} techniques for computing the chemical potential of mol…
The Schottky defect formation energy in MgO calculated by diffusion Monte Carlo
D. Alfè, M. J. Gillan
The energetics of point defects in oxide materials plays a major role in determining their high-temperature properties, but experimental measurements are difficult, and calculation…
Quantum Monte Carlo calculations of the structural properties and the B1-B2 phase transition of MgO
D. Alfè, M. Alfredsson, J. Brodholt +2
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-particl…
Diamond and -tin structures of Si studied with quantum Monte Carlo calculations
D. Alfè, M. J. Gillan, M. D. Towler +1
We have used diffusion quantum Monte Carlo (DMC) calculations to study the pressure-induced phase transition from the diamond to -tin structure in silicon. The calculations empl…
An efficient localized basis set for quantum Monte Carlo calculations on condensed matter
D. Alfè, M. J. Gillan
We present an efficient scheme for representing many-body wavefunctions in quantum Monte Carlo (QMC) calculations. The scheme is based on B-splines (blip functions), which consist…
Linear-scaling quantum Monte Carlo with non-orthogonal localized orbitals
D. Alfe`, M. J. Gillan
We have reformulated the quantum Monte Carlo (QMC) technique so that a large part of the calculation scales linearly with the number of atoms. The reformulation is related to a rec…
The particle-in-cell model for ab initio thermodynamics: implications for the elastic anisotropy of the Earth's inner core
C. M. S. Gannarelli, D. Alfe, M. J. Gillan
We assess the quantitative accuracy of the particle-in-cell (PIC) approximation used in recent ab initio predictions of the thermodynamic properties of hexagonal-close-packed iron…
Electron correlation and the phase diagram of Si
D. Alfè, M. J. Gillan
Previous first-principles calculations of the melting properties of Si, based on the local-density approximation (LDA) for electronic exchange-correlation energy, under-predict the…
Complementary approaches to the ab initio calculation of melting properties
D. Alfe`, M. J. Gillan, G. D. Price
Several research groups have recently reported {\em ab initio} calculations of the melting properties of metals based on density functional theory, but there have been unexpectedly…
Ab-initio chemical potentials of solid and liquid solutions and the chemistry of the Earth's core
D. Alfe`, M. J. Gillan, G. D. Price
A general set of methods is presented for calculating chemical potentials in solid and liquid mixtures using {\em ab initio} techniques based on density functional theory (DFT). Th…
Thermodynamic stability of Fe/O solid solution at inner-core conditions
D. Alfe`, G. D. Price, M. J. Gillan
We present a new technique which allows the fully {\em ab initio} calculation of the chemical potential of a substitutional impurity in a high-temperature crystal, including harmon…
Thermodynamics of hexagonal-close-packed iron under Earth's core conditions
D. Alfe`, G. D. Price, M. J. Gillan
The free energy and other thermodynamic properties of hexagonal-close-packed iron are calculated by direct {\em ab initio} methods over a wide range of pressures and temperatures r…
Structure and Dynamics of Liquid Iron under Earth's Core Conditions
D. Alfe`, G. Kresse, M. J. Gillan
First-principles molecular dynamics simulations based on density-functional theory and the projector augmented wave (PAW) technique have been used to study the structural and dynam…