Quantum Monte Carlo simulations of solids
- W. Foulkes, L. Mitas, R. Needs, G. Rajagopal
- Physics
- 2001
This article describes the variational and fixed-node diffusion quantum Monte Carlo methods and how they may be used to calculate the properties of many-electron systems. These stochastic…
Structure of phase III of solid hydrogen
- C. Pickard, R. Needs
- Physics, Chemistry
- 1 July 2007
Hydrogen, being the first element in the periodic table, has the simplest electronic structure of any atom, and the hydrogen molecule contains the simplest covalent chemical bond. Nevertheless, the…
Ab initio random structure searching
- C. Pickard, R. Needs
- ChemistryJournal of Physics: Condensed Matter
- 20 January 2011
This work describes a simple, elegant and powerful approach to searching for structures with DFT, which it calls ab initio random structure searching (AIRSS).
Hydrogen Clathrate Structures in Rare Earth Hydrides at High Pressures: Possible Route to Room-Temperature Superconductivity.
- Feng Peng, Ying Sun, C. Pickard, R. Needs, Qiang Wu, Yanming Ma
- PhysicsPhysical Review Letters
- 8 September 2017
It is found that high-temperature superconductivity is closely associated with H clathrate structures, with large H-derived electronic densities of states at the Fermi level and strong electron-phonon coupling related to the stretching and rocking motions of H atoms within the cages.
High-pressure hydrogen sulfide from first principles: a strongly anharmonic phonon-mediated superconductor.
- I. Errea, M. Calandra, F. Mauri
- Physics, Materials SciencePhysical Review Letters
- 10 February 2015
First-principles calculations are used to study structural, vibrational, and superconducting properties of H2S and H3S and show that High-pressure hydrogen sulfide is a strongly anharmonic superconductor.
High-pressure phases of group-IV, III–V, and II–VI compounds
Advances in the accuracy and efficiency of first-principles electronic structure calculations have allowed detailed studies of the energetics of materials under high pressures. At the same time,…
High-pressure phases of silane.
- C. Pickard, R. Needs
- Physics, ChemistryPhysical Review Letters
- 19 April 2006
The high-pressure phases of silane SiH4 are predicted using first-principles electronic structure methods and it is predicted that silane will metallize at higher pressures than previously anticipated but might show high-temperature superconductivity at experimentally accessible pressures.
Inhomogeneous backflow transformations in quantum Monte Carlo calculations.
- P. López Ríos, A. Ma, N. Drummond, M. Towler, R. Needs
- PhysicsPhysical review. E, Statistical, nonlinear, and…
- 18 December 2006
It is found that inhomogeneous backflow transformations can provide a substantial increase in the amount of correlation energy retrieved within VMC and DMC calculations.
Quantum Monte Carlo study of the three-dimensional spin-polarized homogeneous electron gas
- G. G. Spink, R. Needs, N. Drummond
- Physics
- 22 July 2013
We have studied the spin-polarized three-dimensional homogeneous electron gas using the diffusion quantum Monte Carlo method, with trial wave functions including backflow and three-body correlations…
Structures and stability of calcium and magnesium carbonates at mantle pressures
- C. Pickard, R. Needs
- Geology
- 12 July 2014
We acknowledge financial support from the Engineering and Physical Sciences Research Council United Kingdom (EPSRC) of the United Kingdom.
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