QMCPACK

QMCPACK performs ab initio Quantum Monte Carlo (QMC) simulations to compute high-precision electronic structure properties of molecules and materials.

Key Features:

• Auxiliary-Field Quantum Monte Carlo (AFQMC) Enhancements: AFQMC implementation includes k-point symmetries and tensor-hypercontraction to reduce scaling and memory requirements and enable inclusion of more orbitals.
• GPU Acceleration: Accelerated graphical processing unit (GPU) support increases computational throughput for QMC simulations.
• Real-Space Method Advancements: Real-space methods improve bandgap calculations and systematically refine nodal surfaces of ground state wavefunctions to support benchmarking of approximate methods such as GW and DFT.
• Correlation-Consistent Effective Core Potentials: A new set of correlation-consistent effective core pseudopotentials provides improved accuracy and compatibility with many-body applications beyond QMC.

Scientific Applications:

• High-precision electronic structure: Calculation of electronic properties for molecules and materials using QMC approaches.
• Validation of approximate methods: Benchmarking and validation of GW and density functional theory (DFT) results.
• Bandgap calculations: Accurate computation of bandgaps in materials.
• Ground state wavefunction analysis: Investigation and systematic improvement of nodal surfaces of ground state wavefunctions.

Methodology:

Implements AFQMC with k-point symmetries and tensor-hypercontraction, real-space QMC methods, GPU-accelerated computation, and the use of correlation-consistent effective core pseudopotentials, with integration support for Nexus workflows.