Volume 11 Issue 11
First Principles Methods: A Perspective from Quantum Monte Carlo
Miguel A. Morales,Raymond Clay,Carlo Pierleoni andDavid M. Ceperley
1Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550, USA
2Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street Urbana, IL 61801-3080, USA
3Dipartimento di Scienze Fisiche e Chimiche, Università de L’Aquila, Via Vetoio 10,L’Aquila 67100, Italy
4Dipartimento di Fisica, Sapienza Università di Roma, P.le A. moro 2, Rome 00185, Italy
*Author to whom correspondence should be addressed.
Abstract
Quantum Monte Carlo methods are among the most accurate algorithms for predicting properties of general quantum systems. We briefly introduce ground state, path integral at finite temperature and coupled electron-ion Monte Carlo methods, their merits and limitations. We then discuss recent calculations using these methods for dense liquid hydrogen as it undergoes a molecular/atomic (metal/insulator) transition. We then discuss a procedure that can be used to assess electronic density functionals, which in turn can be used on a larger scale for first principles calculations and apply this technique to dense hydrogen and liquid water.Keywords: quantum Monte Carlo; first-principles simulations; hydrogen; Coupled Electron-Ion Monte Carlo; high pressure