ORCA 6 Changes

Highlights

SCF and Single Reference

  • LeanSCF: reduced memory, more robust convergence

  • Electric field optimizations

  • General ROHF implementation (SCF/Gradient) with all approximations

  • General CSF ROHF

  • New density functionals

  • Delta-SCF

  • UHF STEOM-CCSD

  • UHF-IP-EOM-CCSD

  • UHF-EA-EOM-CCSD

  • Regularized OOMP2

  • Solvation in OOMP2

  • Improved stability analysis featuring all approximations, solvation etc

  • MixGuess to converge to biradicaloid open shell singlet type broken symmetry solutions

  • Approximate Spin Projection Method for broken symmetry calculations (SCF/Gradient)

Multi Reference

  • TRAH, AVAS, MCRPA

  • Linear response CASSCF

  • Vastly improved Recursive CI coupling coefficient generation

Automatic Code generation

  • MPn

  • CCSD(T) gradients

  • CCSDT

Relativity

  • X2C

  • New and consistent DKH infrastructure

Solvation & Embedding

  • DLPNO-CCSD(T) PTES Approach

  • SMD analytical Hessian

  • Dynamically adjusted radii: DRACO

  • Improved surface grids

  • Interface to openCOSMO-RS

  • Explicit Solvator

  • Molecule Docker

  • FMM implementation for embedding

  • CIM implementation works with DLPNO-CC, DLPNO-MP2

Optimization

  • More robust optimizer (fewer cycles, fewer cases with negative frequencies)

  • GOAT global optimizer and conformer generator

  • Basis set limit extrapolated optimizations through compound scripts

  • Extrapolation with counterpoise correction through compound scripts

Hessian

  • Group parallelization

  • Performance improvements

Excited States

  • Analytical gradient for meta-GGA functionals

New Spectroscopic Properties

  • VCD implementation at the SCF level

  • MCD with vibronic structure

  • General spin ROCIS

  • Higher order moments and exact field matter coupling

  • Spin rotation constants

Misc Properties

  • Local dipole moments and polarizabilities

  • Frequency dependent electric properties

  • VPT2 enhancements

  • Restructured NMR simulation program orca_nmrspectrum

  • MBIS charges

Workflow & Interfacing

  • Property file: Machine readable, Human readable summary of ORCA run

  • Compound: vastly improved Syntax, features, optimizations, …

  • orca_2json: generate integrals, property file, run backwards to get MOs into ORCA

  • Citation tool for helping find the right references

Other Changes

SCF and Infrastructure

  • Significant improvements to the SOSCF solver to make it more robust, preventing huge steps that break the SCF. Overall improvements on the DIIS solvers.

  • Due to the SCF updates, the AutoTRAH is now not so often needed and will start now only from above 50 cycles (AutoTRAHIter).

  • Improvements to the memory handling of TD-DFT, CP-SCF and the Hessian

Basis sets

  • def-TZVP and ma-def-TZVP pseudo-potential basis sets for the actinides (Z = 89, Ac - 103, Lr)

  • Lehtola’s hydrogenic gaussian basis set family (HGBS) including polarized (HGBSP) and augmented (AHGBS, AHGBSP) variants for all elements up to Oganesson (Z = 118)

  • def2-SVPD, def2-TZVPD, def2-TZVPPD, def2-QZVPD, def2-QZVPPD basis sets for lanthanoids

  • !MINIX now correctly activates the corresponding ECP

  • Added user-specified L-limit to AutoAux AutoAuxLLimit

  • Fixed segfault in dhf-ECP

  • Fix for DelECP in %coords

  • Added ReadFragBasis keywords read fragment-specific basis sets from a file

Solvation

  • New charge correction / compensation algorithm (corrected charges printed in an additional file)

  • C-PCM/B scheme for QM/MM calculations

  • DDCOSMO and CPCM/X available for XTB calculations and QM/MM calculations

  • Generalization of names within all solvation models (C-PCM/SMD/ALPB/DDCOSMO/CPCM-X)

  • New discretization scheme for the cavity (C-PCM) based on a constant number of charges per unit of area

DFT

  • Allow LibXC functional customization via external parameters

  • Simple input keywords added for some LibXC functionals

  • Added wB97M(2) functional parameters: must be used with wB97M-V orbitals in a two-step job (compound script available)

  • Bugfixes for LibXC combined *_xc_* functionals

  • Fixed crash for D4 + ghost atoms

Excited states

  • Analytical gradient for meta-GGA functionals

  • Small bugfix to spin-adapted triplets and NACMEs.

  • The FolllowIRoot for excited state optimization uses now a much more robust algorithm.

Relativity

  • Enabled NumGrad with relativistic methods

  • Second order DKH picture-change correction of contact density

  • Minor fixes in DKH picture-change corrections of magnetic properties

  • Picture change corrections are activated automatically

Multiscale

  • Reading PDB files for 10k+ atoms with HETATMs now possible

  • Enabled correct FlipSpin behavior with QMMM

  • More efficient MM Module

  • Implemented wall potential

Coupled cluster / DLPNO

  • Implemented energy ordering for PNO generation

  • Added semicore treatment for DLPNO

  • Enable DLPNO-CCSD(T) calculations to run DLPNO-CCSD unrelaxed densities

MP2

  • Corrected memory estimates and batching in response and gradient

  • Removed the slow and limited analytic (RI-)MP2 Hessian code

  • Removed non-default Gamma-in-core option for RI-MP2 response

  • Disabled single-precision calculations

  • Disabled SemiDirect option in AO-MP2

  • Enabled range-separated DHDFT gradients with RIJDX

NEB

  • Improved IDPP initial path

  • More efficient GFN-xTB runs for NEB

COSX

  • Improvements to numerical integration grids, both for DFT and COSX

  • Faster grid step

  • Improved performance and accuracy in COSX, also for the gradient and Hessian

Properties

  • NMR spin-spin coupling:

    • Added SpinSpinElemPairs and SpinSpinAtomPairs keywords to limit which couplings are computed

    • Reduced the number of CP-SCF perturbations necessary via a stochastic selection

    • DSO term was transposed.

    • Off-diagonal PSO elements had the wrong sign

    • Efficiency improvement: solve SD/FC CP-SCF equations in restricted mode for RHF, instead of always using UHF

  • Optimized numeric integration for HFC gauge correction

  • Removed RITRAFO option for CP-SCF

  • Switched to tau=Dobson as default handling of the kinetic energy density in meta-GGA magnetic properties with GIAOs

Hessian

  • Improvements to the Hessian to avoid accumulation on numerical noise and reduce the number of spurious negative frequencies.

Geometry Optimization

  • Several improvements to the geometry optimization, making is much more stable. Complete redesign of the Cartesian optimizer (!COPT), making it quick enough to be used together with faster methods.

  • Fallbacks in the geometry optimization in case something fails, e.g. if the internal coordinates are unacceptable.

  • Arbitrary spherical, ellipsoidal or box-like wall potentials can be added, which will reflect on the energy and gradients and can be used during geometry optimization.

Miscellaneous

  • CHELPG charges that reproduce the ESP together with the molecular dipole moment

  • Fixed issues with constraints in multi-step jobs

  • Molden output: store ECP info in [Pseudo] block, set point charge atomic number to 0, handling of ghost atoms

  • Made the ExtOpt interface easier to use

  • Store energy from NEB and IRC in the XYZ file