137 citations · 671 across the 11 of their papers we have counts for
11 papers
Phase transitions and spin-state of iron in FeO at the conditions of Earth's deep interior
E. Greenberg, R. Nazarov, A. Landa +8
Iron-bearing oxides undergo a series of pressure-induced electronic, spin and structural transitions that can cause seismic anomalies and dynamic instabilities in Earth's mantle an…
Diffusion quantum Monte Carlo study of the equation of state and point defects in aluminum
Randolph Q. Hood, P. R. C. Kent, Fernando A. Reboredo
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…
Systematic reduction of sign errors in many-body calculations of atoms and molecules
Michal Bajdich, Murilo L. Tiago, Randolph Q. Hood +2
The self-healing diffusion Monte Carlo algorithm (SHDMC) [Phys. Rev. B {\bf 79}, 195117 (2009), {\it ibid.} {\bf 80}, 125110 (2009)] is shown to be an accurate and robust method fo…
Self-healing diffusion quantum Monte Carlo algorithms: methods for direct reduction of the fermion sign error in electronic structure calculations
Fernando A. Reboredo, Randolph Q. Hood, Paul R. C. Kent
We develop a formalism and present an algorithm for optimization of the trial wave-function used in fixed-node diffusion quantum Monte Carlo (DMC) methods. We take advantage of a b…
Neutral and charged excitations in carbon fullerenes from first-principles many-body theories
Murilo L. Tiago, P. R. C. Kent, Randolph Q. Hood +1
We investigate the accuracy of first-principles many-body theories at the nanoscale by comparing the low energy excitations of the carbon fullerenes C_20, C_24, C_50, C_60, C_70, a…
Comparative study of density functional theories of the exchange-correlation hole and energy in silicon
A. C. Cancio, M. Y. Chou, Randolph Q. Hood
We present a detailed study of the exchange-correlation hole and exchange-correlation energy per particle in the Si crystal as calculated by the Variational Monte Carlo method and…
Two-dimensional limit of exchange-correlation energy functional approximations in density functional theory
Yong-Hoon Kim, In-Ho Lee, Satyadev Nagaraja +3
We investigate the behavior of three-dimensional (3D) exchange-correlation energy functional approximations of density functional theory in anisotropic systems with two-dimensional…
Symmetry Constraints and Variational Principles in Diffusion Quantum Monte Carlo Calculations of Excited-State Energies
W. M. C. Foulkes, Randolph Q. Hood, R. J. Needs
Fixed-node diffusion Monte Carlo (DMC) is a stochastic algorithm for finding the lowest energy many-fermion wave function with the same nodal surface as a chosen trial function. It…
Finite size errors in quantum many-body simulations of extended systems
P. R. C. Kent, Randolph Q. Hood, A. J. Williamson +3
Further developments are introduced in the theory of finite size errors in quantum many-body simulations of extended systems using periodic boundary conditions. We show that our re…
Quantum Monte Carlo calculations of the one-body density matrix and excitation energies of silicon
P. R. C. Kent, Randolph Q. Hood, M. D. Towler +2
Quantum Monte Carlo (QMC) techniques are used to calculate the one-body density matrix and excitation energies for the valence electrons of bulk silicon. The one-body density matri…
Diffusion Quantum Monte Carlo Calculations of Excited States of Silicon
A. J. Williamson, Randolph Q. Hood, R. J. Needs +1
The band structure of silicon is calculated at the Gamma, X, and L wave vectors using diffusion quantum Monte Carlo methods. Excited states are formed by promoting an electron from…