Energy calculations
NC-MRSF energies
Planned energy calculations with noncollinear mixed-reference spin-flip TDDFT.
OpenQP releases
Know what is in your version.
From the MRSF-TDDFT foundation to spectroscopy, correlated methods and molecular dynamics. Explore released capabilities separately from the next release.
Upcoming · In development
OpenQP 1.4
New MRSF energies. Faster calculations. Molecular dynamics in complex environments.
The next OpenQP release is planned around NC-MRSF and CVC-MRSF energy calculations, MRSF performance improvements, and accumulated bug fixes and reliability improvements for QM/MM nonadiabatic molecular dynamics.
Energy calculations
CVC-MRSF energies
Planned energy calculations with core–virtual-completed MRSF-TDDFT.
Performance development
MRSF performance
Further improvements to MRSF calculation efficiency. Release-specific benchmarks will document the supported systems and hardware.
Bug fixes & dynamics
QM/MM NAMD reliability
Accumulated QM/MM bug fixes, including covalent-boundary charge treatment, ESPF calculations, and molecular-dynamics controls.
QM/MM fixes and improvements targeted for 1.4
- Covalent QM/MM boundaries: charge redistribution at a cut bond addresses the artificial attraction between a link atom and its charged MM neighbour.
- ESPF calculations: revised operator evaluation and bounded temporary storage improve the treatment of larger QM regions.
- Dynamics controls: clearer separation of nuclear propagation, electronic-state dynamics and QM/MM settings, with restart and snapshot handling.
These selected changes have accumulated since 1.3.1. Final release notes will identify the included fixes and compatibility changes.
In development · Release date to be announced. Final capabilities and supported combinations will be confirmed in the 1.4 release notes.
NC-MRSF and CVC-MRSF are planned here for energy calculations; this preview does not announce their analytic gradients or their use in dynamics. QM/MM and NAMD already exist in the 1.2.1 and 1.3 families; the 1.4 direction is their further development.
The planned 1.4 academic binary edition has a limit of 32 OpenMP threads per calculation. Higher-capacity individual use and computing-centre deployment require the appropriate licence. This planned limit starts with 1.4 and does not change permissions for earlier copies. Final distribution terms will accompany the release.
Academic, computing-centre and commercial enquiries →Released family · 13 August 2026
OpenQP 1.3
Correlation and molecular dynamics
The 1.3 family broadens correlated electronic-structure calculations and strengthens MRSF state analysis, nonadiabatic dynamics, and QM/MM calculations.
Electronic structure
- Closed- and open-shell CCSD(T), with frozen-core and Cholesky-based calculation options.
- FCI, CASCI, CASSCF and state-averaged CASSCF, together with CASPT2, NEVPT2 and QDPT2 methods. Method-specific energy and derivative support must be checked against the exact release.
- MRSF physical-state analysis, symmetry labels, and orbital exports.
Dynamics and geometry
- Continued MRSF NAMD and SOC-NAMD development, including electronic-state tracking and restart consistency.
- QM/MM dynamics, finite-water-droplet boundary controls, and further SOC-NAMD/QM/MM integration.
- Geometry and symmetry improvements, including robust internal coordinates.
1.3.1 update
- Windows x86-64 support alongside Linux and macOS builds.
- Analytic nuclear gradients for RHF MP2, state-specific and state-averaged CASSCF, SC-NEVPT2, CASPT2 and XMS-CASPT2, as documented in the release notes.
- Compiler, packaging and numerical corrections. Consult the binary download notes for platform requirements and known limitations; the distributed 1.3.1 binaries do not include PCM/ddX.
1.3.0 was released on 13 August 2026; 1.3.1 followed on 21 August 2026. Research License 1.0 applies to these releases. Existing copies retain their original terms.
Released family · 25 June 2026
OpenQP 1.2
Properties, spectroscopy and practical calculations
The 1.2 family extends the MRSF foundation with molecular properties, spectroscopy, geometry calculations, and more convenient input and Python tools.
1.2.0 properties and methods
- MRSF-EKT ionization potentials, electron affinities and Dyson-orbital output; one- and two-electron MRSF spin–orbit coupling.
- Analytic HF/DFT Hessians, vibrational frequencies and intensities, and GIAO NMR shieldings.
- Energy-only ddPCM continuum solvation; spherical-harmonic basis functions and point-group symmetry.
Geometry and numerical methods
- Built-in geometry optimisation, transition-state and crossing searches, and reaction-path calculations.
- Improved initial guesses, SCF convergence, DFT integration grids, and OpenMP work distribution.
- Linux and macOS packaging in 1.2.0; Windows installers were not included in that release.
1.2.1 update
- Readable .oqp inputs and a high-level Python API; standalone MP2 and spin-component-scaled variants.
- MRSF surface-hopping NAMD, SOC-NAMD and ESPF QM/MM through OpenMM, including combined SOC-NAMD-QM/MM calculations.
- MRSF state and transition density analysis, and additional QM/MM covalent-boundary controls.
1.2.0 was released on 25 June 2026; 1.2.1 followed on 18 July 2026. These historical release copies retain their accompanying GPLv3 terms. Their terms are not changed by the planned 1.4 policy.
Released family · 11 March 2025
OpenQP 1.0
The MRSF-TDDFT foundation
The inaugural OpenQP release establishes the Fortran calculation engine and Python tools for ground- and excited-state quantum chemistry centred on MRSF-TDDFT.
Ground and excited states
- HF and DFT ground-state calculations with LibXC functionals.
- MRSF-TDDFT and DTCAM-series functionals for multiconfigurational ground and excited electronic states.
- MRSF nonadiabatic-coupling calculations for photochemical applications.
Molecular structures
- Geometry optimisation, transition-state searches and conical-intersection searches using SciPy and DL-Find.
- DFT-D4 dispersion corrections and Molden-format output for molecular visualisation.
- Python scripting through PyOQP, with OpenMP/MPI parallel execution and BLAS/LAPACK integration.
Released on 11 March 2025. This is a historical capability summary, not a current installation guide. Later SOC and MRSF-EKT features must not be inferred from the 1.0 roadmap. The original GPLv3 terms remain attached to existing copies.
Choose the exact release for your calculation
These summaries describe release families, including the patch versions explicitly identified above. A method in the source tree is not a guarantee that every distributed binary includes its optional libraries. Check the release notes, installed version and build capabilities before starting a calculation.
Version 1.1 was released between 1.0 and 1.2 and added ECP support, SCF convergence improvements, UMRSF energies and XAS examples. It is not an omitted upgrade step when comparing the families above.