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ORCA 6.1 Manual
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ORCA 6.1 Manual
  • Versions
    • 6.1
    • 6.0

Preface

  • ORCA 6.1.1 Foreword
  • ORCA 6.1.0 Foreword
  • ORCA 6.1 Highlights
  • How to cite
  • How to use this manual

Main Part

  • 1. Quickstart Guide
    • 1.1. About ORCA
    • 1.2. Installation
    • 1.3. Graphical User Interfaces (GUI)
    • 1.4. Running ORCA
    • 1.5. Hello water! Your first ORCA calculation
    • 1.6. General Recommendations
    • 1.7. Troubleshooting Problems in ORCA
  • 2. Essential Calculation Elements
    • 2.1. General Structure of the Input File
    • 2.2. Input of Coordinates
    • 2.3. Basic Calculation Settings
    • 2.4. Control of Output
    • 2.5. Parallel and Multi-Process Runs
    • 2.6. Self-Consistent-Field (SCF)
    • 2.7. Basis Sets
    • 2.8. Resolution-of-the-Identity (RI)
    • 2.9. Numerical Integration
    • 2.10. Details on the Numerical Integration Grids
    • 2.11. Counterpoise Corrections
    • 2.12. Relativistic Calculations
    • 2.13. Implicit Solvation
    • 2.14. Integral Handling
    • 2.15. The SHARK Integral Package and Task Driver
    • 2.16. SCF Stability Analysis
    • 2.17. Finite Electric Fields
    • 2.18. Fragment Specification
    • 2.19. ORCA and Symmetry
    • 2.20. Choice of Initial Guess and Restart of SCF Calculations
    • 2.21. Frozen Core Options
    • 2.22. CP-SCF Options
    • 2.23. Numerical Gradients
  • 3. Model Chemistries
    • 3.1. Wavefunction Types: RHF/RKS, UHF/UKS, ROKS and more
    • 3.2. Hartree Fock Theory
    • 3.3. Density Functional Theory (DFT)
    • 3.4. Dispersion Corrections
    • 3.5. Semiempirical Methods
    • 3.6. Composite Methods (3c methods)
    • 3.7. Analytic Density Functional Theory (ADFT)
    • 3.8. Random Phase Approximation (RPA)
    • 3.9. Perturbation Theory - MP2
    • 3.10. Coupled Cluster and CI Theories (MDCI)
    • 3.11. Correlated Methods using Automatic Code Generation (AUTOCI)
    • 3.12. Arbitrary Order Coupled-Cluster (MRCC interface)
    • 3.13. Complete and Incomplete Active Space Self-Consistent Field (CASSCF and RAS/ORMAS)
    • 3.14. Approximate Full CI Calculations in Subspace: ICE-CI
    • 3.15. Density Matrix Renormalization Group (DMRG)
    • 3.16. N-Electron Valence State Perturbation Theory (NEVPT2)
    • 3.17. Complete Active Space Peturbation Theory (CASPT2 and CASPT2-K)
    • 3.18. CASSCF and DFT
    • 3.19. Multireference Configuration Interaction and Pertubation Theory (uncontracted)
    • 3.20. Multireference Equation of Motion Coupled-Cluster (MR-EOM-CC)
    • 3.21. Dynamic Correlation Dressed CAS
    • 3.22. Full Configuration Interaction
    • 3.23. Molecular Mechanics
  • 4. Structure and Reactivity
    • 4.1. Geometry Optimizations
    • 4.2. Surface Scans
    • 4.3. Transition State Searches
    • 4.4. Intrinsic Reaction Coordinate
    • 4.5. Nudged Elastic Band Method
    • 4.6. Vibrational Frequencies
    • 4.7. Thermochemistry
    • 4.8. Conical Intersections
    • 4.9. Minimum Energy Crossing Points (MECP)
    • 4.10. GOAT: global geometry optimization and ensemble generator
    • 4.11. SOLVATOR: Automated Explicit Solvation
    • 4.12. DOCKER: Automated Docking Algorithm
  • 5. Spectroscopy and Properties
    • 5.1. Population Analysis
    • 5.2. Natural Bond Orbital (NBO) Analysis
    • 5.3. Fractional Occupation Number Weighted Density (FOD)
    • 5.4. Excited States Calculations
    • 5.5. Excited State Dynamics
    • 5.6. Excited States via RPA, CIS, TD-DFT and SF-TDA
    • 5.7. Excited States via ROCIS and ROCIS/DFT
    • 5.8. Excited States via MCRPA
    • 5.9. Excited States via EOM-CCSD
    • 5.10. Excited States via STEOM-CCSD
    • 5.11. Excited States via IH-FSMR-CCSD
    • 5.12. Excited States via PNO-based coupled cluster
    • 5.13. Excited States via DLPNO-STEOM-CCSD
    • 5.14. One Photon Spectroscopy
    • 5.15. Core-Level Spectroscopy with Coupled Cluster Methods
    • 5.16. Simulation and Fit of Vibronic Structure in Electronic Spectra, Resonance Raman Excitation Profiles and Spectra with the orca_asa Program
    • 5.17. Absorption and Fluorescence Bandshapes using ORCA_ASA
    • 5.18. Vibrational Spectroscopy
    • 5.19. Anharmonic Analysis and Vibrational Corrections using VPT2/GVPT2 and orca_vpt2
    • 5.20. Electrical Properties - Electric Moments and Polarizabilities
    • 5.21. Nuclear Magnetic Resonance (NMR) Parameters
    • 5.22. Electron Paramagnetic Resonance (EPR) Parameters
    • 5.23. MP2 Level Magnetic Properties
    • 5.24. CASSCF Linear Response
    • 5.25. Mössbauer Parameters
    • 5.26. The Spin-Orbit Coupling Operator
    • 5.27. Broken-Symmetry Wavefunctions and Exchange Couplings
    • 5.28. Decomposition of the Magnetic Exchange Coupling
    • 5.29. Magnetic Properties Through Quasi Degenerate Perturbation Theory
    • 5.30. Magnetic Relaxation
    • 5.31. Simulation of (Magnetic) Circular Dichroism and Absorption Spectra
    • 5.32. Interface to SINGLE_ANISO Module
    • 5.33. Interface to POLY_ANISO Module
    • 5.34. DeltaSCF
    • 5.35. Extended Transition State with Natural Orbitals for Chemical Valence (ETS-NOCV/EDA-NOCV)
    • 5.36. Local Energy Decomposition
    • 5.37. The Hartree-Fock plus London Dispersion (HFLD) Method
    • 5.38. ADLD(D): Atomic Decomposition of DFT-D London Dispersion Energy
    • 5.39. Static Ground State DFT (SGS-DFT)
  • 6. Multiscale Simulations
    • 6.1. Overview on ORCA’s Multiscale Implementation
    • 6.2. Multiscale Simulations of molecular systems
    • 6.3. CRYSTAL-QMMM
    • 6.4. QM/MM via Interfaces to ORCA
    • 6.5. Fast Multipole Method
  • 7. Molecular Dynamics
    • 7.1. Ab initio Molecular Dynamics
  • 8. Workflows and Automatization
    • 8.1. ORCA Python Interface (OPI)
    • 8.2. Compound
    • 8.3. More Details on Compound
    • 8.4. Compound Examples
  • 9. Utilities and Visualization
    • 9.1. Orbital and Density Plots
    • 9.2. Utility Programs
    • 9.3. orca_2json
    • 9.4. Property File
  • 10. Architecture of ORCA
    • 10.1. ORCA Structure
    • 10.2. The Architecture of ORCA
    • 10.3. Units and Conversion Factors

Appendix

  • 1. Detailed change log
  • 2. Publications Related to ORCA
  • 3. Glossary

Bibliography & Index

  • Bibliography
  • Index
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Versions¶

  • 6.1
  • 6.0
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ORCA 6.1.1 Foreword
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