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ORCA Version 4.1 released

 

With the release of ORCA 4.1, they have moved our forum and download site to a new server at the Max Planck Institute fuer Kohlenforschung, where the ORCA team now has its home base. Now at https://orcaforum.kofo.mpg.de.

ORCAis an ab initio quantum chemistry program package that contains modern electronic structure methods including density functional theory, many-body perturbation, coupled cluster, multireference methods, and semi-empirical quantum chemistry methods. Its main field of application is larger molecules, transition metal complexes, and their spectroscopic properties. DOI.

List of new features for ORCA 4.1:

SCF/DFT

  • B97M-V, wB97M-V, wB97X-V plus various D3 variants of B97 functionals
  • Simple input keywords for DSD-BLYP, DSD-PBEP86, and DSD-PBEB95
  • CPCM analytic Hessian
  • DLPNO-double hybrid DFT including gradient
  • SymRelax option in %method

Semiempirical methods

  • XTB method of Grimme et al.

Coupled cluster

  • Iterative solution of the full (T) equations for DLPNO-CCSD(T)
  • Open shell DLPNO-CCSD density and spin density matrices
  • Full DLPNO-MP2 gradient
  • CIM (Cluster in molecules) Implementation with MP2, CCSD(T), DLPNO-MP2 and DLPNO-CCSD(T)
  • IP and EA coupled cluster methods and their DLPNO variants
  • STEOM-CCSD for open shells
  • SOC between bt-PNO-STEOM and STEOM states
  • Improved Multilevel implementation including multilevel DLPNO-IP
  • F12-Triples scaling for RHF canonical CCSD(T) based on the CCSD/ CCSD-F12 ratio

Multireference

  • New CASSCF SuperCIPT converger is reliable and efficient.
  • New options for final orbitals to find partner orbitals for the chosen active space e.g. bonding / anti-bonding partners.
  • MC-RPA (Multiconfigurational random phase approximation)
  • ◦ AO driven integral direct for calculations on larger molecules
  • ◦ Fock matrix -> conventional, direct, RIJ/COSX
  • ◦ MPI parallel
  • ◦ NTOs for visualizing transitions
  • Checking stability of state specific CASSCF wave functions by orca_mcrpa
  • Dynamic correlation dressed (DCD-CAS) method with inclusion of relativistic effects (SOC, spin-spin, magnetic fields)
  • CASSCF RIJCOSX allows two separate auxiliary basis sets
  • CASCI/NEVPT2 protocol for XAS and RIXS

Optimization

  • Nudge elastic band method to locate transition states
  • Enabled 3-dimensional relaxed potential energy surface scan
  • Improvement of redundandant internal coordinate generation
  • Faster and more smooth convergence for 3-dimensional systems and embedded cluster models
  • Intrinsic reaction coordinate (IRC) following
  • Swart model Hessian (good for weak interactions)

Molecular Dynamics

  • MD simulations can now use Cartesian, distance, angle, and dihedral angle constraints.
  • The MD module now features cells of several geometries (cube, orthorhombic, parallelepiped, sphere, ellipsoid), which can help to keep the system inside of a well-defined volume.
  • The cells can be defined as elastic, such that their size adapts to the system. This enables to run simulations under constant pressure.
  • Ability to define regions (subsets of atoms) enables applications such as thermostating different parts of the system to different temperatures (cold solute in hot solvent, temperature gradients, ...)
  • Trajectories can now be written in XYZ and PDF file format.
  • A restart file is written in every simulation step. Simulations can be restarted to seamlessly continue.
  • The energy drift of the simulation is now displayed in every step.
  • The MD module now works with a broader range of methods (semiempirics, ECPs, QM/MM).
  • Fixed a bug in the time integration of the equations of motion which compromised energy conservation.

Spectroscopic properties

  • orca_pnmr module tool to calculate paramagnetic NMR spectra
  • NMR chemical shifts with RI-MP2 and double hybrid DFT including GIAO’s, spin-component scaling and CPCM
  • NMR Spin-Spin coupling in calculations with DFT/HF
  • NMR wth ZORA
  • Maximoff-Scuseria correction for the kinetic energy density in GIAO-based calculations with meta-GGA functionals
  • Exact and gauge invariant transition moments and approximate decomposition into dipole, quadrupole etc terms in all modules.
  • PNO-ROCIS method for more efficient X-ray absorption calculations
  • IP-ROCISD for high spin ROHF references
  • TD-DFT:
  • Transient spectra (excited state absorption) for CIS/TDA
  • Triplet gradients (with RIJ, COSX and all) for all cases.
  • Spin orbit coupling (including CPCM) and gradients
  • Root following scheme for optimization
  • Slow term to correct energy of relaxed excited state
  • Full TD-DFT with double hybrids
  • ESD module to calculate spectroscopic properties
  • Vibrationally resolved absorption spectra including Duschinsky rotation and/or vibronic coupling.
  • Fluorescence and Phosphorescence rates with same options.
  • Resonance Raman spectra with the same options
  • works with CIS/TDDFT, ROCIS, CASSCF and EOM/STEOM.
  • Seven different schemes for obtaining an excited state PES and five different choices of coordinate systems

Analysis tools:

  • Open Shell LED
  • Dispersion interaction Density plots
  • LED for DLPNO-MP2
  • LED for the frozen state
  • Update of AIM interface
  • NBO 7 compatibility (i4)
  • Miscellaneous
  • Compound method (Infrastructure, plus W2.2, W1, G2(MP2), G2(MP2-SVP), G2(MP2-SV) methods)
  • Property file (additional properties, plus new infrastructure)
  • Decomposition of correlation energy for canonical RHF CCSD energies to singlet - triple pairs
  • Additional EP2 extrapolation schemes using RI-MP2 and DLPNO-MP2 methods as cheap methods (request from forum)
  • Lanthanide new def2 basis sets
  • def2-XVP/C auxiliary basis sets for Ce-Lu by Chmela and Harding.
  • Robust Second order optimizer for localized orbitals
  • Added a few basis sets.

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