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New ORCA Release: ORCA 4.2.0

  1. Local correlation
    • Iterative (T) for open shells
    • Multi-level scheme for open shell systems (all PNO accuracy levels)
    • DLPNO-STEOM-CCSD for closed shells
    • DLPNO-CCSD(T)-F12 for open shells
    • Automatic fragmentation in LED analysis
    • RIJCOSX-LED implementation
    • HF-LD method for efficient dispersion energy calculations
  2. Multi-Reference
    • FIC-CASPT2 implementation including level shift and IP/EA shift.
    • FIC-NEVPT2 unrelaxed densities and natural orbitals.
    • CIPSI/ICE improvements. Can be run now with configurations, individual determinants or CSFs (experimental)
    • FIC-ACPF/AQCC: variants of the FIC-MRCI ansatz
    • Efficient linear response CASSCF
    • Reduced memory requirements in MRCI and CIPSI/ICE
  3. Spectroscopy
    • GIAO EPR calculations (one issue with the SOMF operator still remaining)
    • Improvements to ESD module for fluorescence, phosphorescence, bandshape, lifetime and resonance Raman calculations
    • ESD now includes also the prediction of the Intersystem Crossing non-radiative rates
    • Hyperfine couplings for CASSCF calculations (but not as response)
  4. Excited states
    • Spin-orbit coupling in TD-DFT
    • MECP optimization for TD-DFT
    • Conical Intersection Optimization
    • Range-separated double-hybrids (ωB2PLYP, ωB2GPPLYP) for TDDFT
    • Numerical and Hellmann-Feynman NACMEs using TD-DFT/CIS
    • DLPNO-STEOM-CCSD for closed shells (also see 'Local correlation')
  5. Solvation
    • CPCM Gaussian Charge Scheme with the scaled-vdW surface and the Solvent Excluded Surface (SES). Available for single point energy calculations and geometry optimizations using the analytical gradient.
  6. SCF/optimizer/semi-empirics/infrastructure etc.
    • Nudge elastic band (NEB) transition states improvements (also works with xTB for initial path)
    • Improved compound method scripting language for workflow improvements
    • Improved ASCII property file
    • Libxc interface allows a far wider range of density functionals to be used
    • Interfaced with Grimme’s GFN-xTB and GFN2-xTB
    • Improvement of IRC algorithm
    • Cartesian minimization (L-OPT) for systems with 100.000s of atoms, Minimization of specific elements (incl. H) only, fragment specific optimization treatment (relax all, relax hydrogens, rigid fragment, fixed fragments)
  7. QM/MM and MM
    • First release with ORCA-native MM and QM/MM implementation
    • Automated conversion from NAMD’s CHARMM format
    • Automated generation of simple force-field for non-standard molecules
    • Simple definition of active and QM regions
    • Automated inclusion and placement of link-atoms
    • Automated charge-shifts to prevent over-polarization
    • MM and QM/MM work with all kinds of optimizations, NEB / NEB-TS methods, frequency analysis
    • Option for rigid MM water (TIP3P) in MD simulation and optimization
  8. Molecular Dynamics
    • Added a Cartesian minimization command to the MD module, based on L-BFGS and simulated annealing. Works for large systems (> 10'000 atoms) and also with constraints. Offers a flag to only optimize hydrogen atom positions (for crystal structure refinement).
    • The MD module can now write trajectories in DCD file format (in addition to the already implemented XYZ and PDB formats).
    • The thermostat is now able to apply temperature ramps during simulation runs.
    • Added more flexibility to region definition (can now add/remove atoms to/from existing regions).
    • Added two new constraint types which keep centers of mass fixed or keep complete molecules rigid.
    • Ability to store the GBW file every n-th step during MD runs (e.g. for plotting orbitals along the trajectory).
    • Can now set limit for maximum displacement of any atom in a MD step, which can stabilize dynamics with poor initial structures. Runs can be cleanly aborted by "touch EXIT".
    • Better handling/reporting of non-converged SCF during MD runs.
    • Fixed an issue which slowed down molecular dynamics after many steps.
    • Stefan Grimme's xTB method can now be used in the MD module, allowing fast simulations of large systems.
  9. Miscellaneous
    • Compute thermochemical corrections at different temperatures without recomputing the Hessian
    • Fragments can now be defined in the geom block as simple lists
    • Simpler input format for definition of atom lists and fragments, in particular useful for large atom lists
    • basename.trj files are now called basename_trj.xyz


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