Welcome to MRChem’s documentation!¶
MRChem is a numerical real-space code for molecular electronic structure calculations within the self-consistent field (SCF) approximations of quantum chemistry (Hartree-Fock and Density Functional Theory). The code is divided in two main parts: the MultiResolution Computation Program Package (MRCPP), which is a general purpose numerical mathematics library based on multiresolution analysis and the multiwavelet basis which provide low-scaling algorithms as well as rigorous error control in numerical computations, and the MultiResolution Chemistry (MRChem) program that uses the functionalities of MRCPP for computational chemistry applications.
The code is being developed at the Hylleraas Centre for Quantum Molecular Sciences at UiT - The Arctic University of Norway.
The code is under active development, and the latest stable releases as well as development versions can be found on GitHub.
Features in MRChem-1.0.0:¶
- Wave functions:
- Kohn-Sham DFT
Spin-polarized
Spin-unpolarized
LDA, GGA and hybrid functionals
- Hartree-Fock
Restricted closed-shell
Unrestricted
- Explicit external fields
Electric field
- Properties:
Ground state energy
Dipole moment
Quadrupole moment
Polarizability
Magnetizability
NMR shielding constant
- Parallel implementation:
Shared memory (OpenMP): ~20 cores
Distributed memory (MPI): ~100 procs
Hybrid scheme (MPI + OpenMP): ~1000 cores
- Current size limitations:
~200 orbitals on ~50 medium-memory (64GB) compute nodes
~100 orbitals on a single high-memory (1TB) compute node
Upcoming features:¶
- Wave functions:
Meta-GGAs
ZORA Hamiltonian
Solvent effects
Periodic boundary conditions
External magnetic field
- Properties:
Optical rotation
Spin-spin coupling constant
Hyperfine coupling constant
Magnetically induced currents
Hyperpolarizability
Excitation energies
Geometry optimization
- Performance:
Improved parallel scalability
Improved exact exchange performance
More efficient memory distribution