Introduction to Quantum Monte Carlo - Session 2 of 7

Explore quantum Monte Carlo methods through this comprehensive lecture delivered by Paul Kent as part of the QMCPACK Summer School 2025. Begin with the fundamental electronic structure problem and learn how to solve the Schrödinger equation using quantum Monte Carlo approaches. Understand variational Monte Carlo (VMC) algorithms, including trial wavefunctions, Jastrow factors, and wavefunction optimization techniques through variance and energy minimization methods. Discover how to map VMC calculations to computer implementations and examine practical VMC workflows with real molecular examples. Progress to diffusion Monte Carlo (DMC) methods, covering the fixed node approximation, time step errors, and computational implementation strategies. Analyze comparative examples of DMC and VMC calculations for molecular systems while learning to assess statistical convergence and optimize QMC settings. Master the overall QMC workflow, from initial setup through result analysis, and gain insights into wavefunction quality assessment and accessible system sizes for different computational scenarios. Access supplementary presentation materials and example files through the accompanying GitHub repository to reinforce the theoretical concepts with hands-on practice.