QMCPACK Release v3.15.0 - 2022-09-29

Notes

This is a recommended release for all users. There are many quality of life improvements, bugfixes throughout the application, and updates to the associated testing. Thanks to everyone who reported an issue or suggested an improvement.

We are working to make the performance portable "batched drivers" the default in an upcoming version. These support execution on CPUs and multiple GPU architectures with high performance. Most standard QMC calculations and many observables are already supported. Because some changes to the input files will be required, we recommend trying these drivers now and reporting any issues.

Important bug fix to excited states in splines when spin-up/down sets are built from the same spin species and occupation is specified on the first sposet #4158
The Quantum ESPRESSO converter, pw2qmcpack is now supported via a plugin activated via -DQE_ENABLE_PLUGINS=pw2qmcpack on the QE CMake configure line, see https://qmcpack.readthedocs.io/en/develop/installation.html#quantum-espresso-7-0 . The latest QE 7.1 and earlier 7.0 are supported, and new versions should be automatically compatible.
Substantial improvements to the performance portable / batched implementation. Using LLVM 15.0, high performance production calculations can be performed on NVIDIA GPUs for several wavefunction types, in addition to running on all CPU systems.
As introduced in v3.14.0, the optional project data input parameter driver_version specifies whether legacy or batched drivers are used. In future versions of QMCPACK this tag will be required to avoid ambiguity and allow e.g. the batched VMC driver to be obtained via vmc in addition to vmc_batch. See https://qmcpack.readthedocs.io/en/develop/methods.html#transition-from-classic-drivers
Non-local pseudopotential energy contributions are consistently included in the objective function used for optimization, improving convergence and achievable wavefunction quality e.g. #4177
Support for multistep wavefunction optimization, specifying different parameter sets to be frozen at each step. #4169
Parameter filtration during optimization based on statistical uncertainties #4126
Support for 2D HEG calculations (e.g. #4084 )
Pseudopotential non-local channel can be specified in input #4032
Use of deprecated CUDA texture API removed for greater compatibility #4022
Optimization has been removed from the legacy CUDA code. New calculations needing GPU support should use the batched drivers and their GPU capabilities for optimization. #4138
Initial version of determinant update in SYCL for Intel architectures (e.g. #4118 )
Updated walker counts in several of the performance tests. Due to the changed but more representative workloads, new performance timings should not be compared with older runs (e.g. #4112 )
Maximum system sizes run in the performance tests can be specified in CMake via QMC_PERFORMANCE_NIO_MAX_ATOMS, QMC_PERFORMANCE_C_GRAPHITE_MAX_ATOMS, and QMC_PERFORMANCE_C_MOLECULE_MAX_ATOMS (e.g. #4134 )
Readability refinements in the output, e.g. #4149
UHF/UKS support in PySCF converter #4089
Example installation scripts for more machines placed in config directory, including Archer2, and Polaris.
Many improvements in testing including additional tests, better reliability, and bug fixes.
Minimum version of CMake is now v3.17.0 for CPU builds. For GPU builds, more recent versions may be required. Use of the latest CMake version is generally recommended.
Minimum CUDA version is 11.0 #3957
Minimum version of GCC is now v9.

Nexus

Nexus: support to current batched driver style. Example inputs for batched runs using trial wavefunctions from QE are included in examples/qmcpack/rsqmc_quantum_espresso #4246
Nexus: add override_vp_parameters element #4245
Nexus: fix convert4qmc hdf5 issue #4243
Nexus: extend angular channels for pseudopotentials up to l_max=21 #4148
Nexus: Pass PYTHONPATH recorded at cmake step to nxs-test to ensure tests run #3935
Nexus: Support for VASP keywords to version 6.3 #4056
Nexus: Adding docs for limiting the number of simultaneously submitted jobs to a queue #4133