New Features in Q-Chem 6.4

Q-Chem 6.4 is here! Upgrade and enjoy improved performance and usability, as well as new tools for studying chemistry and spectroscopy. With these new features, you can deploy large-scale calculations and workflows, get more accurate results faster, and extend the scope of your research to include systems and research questions that were not previously accessible.

Check out our list of highlighted features below. Request a free demo to try these features yourself!

  • Spectroscopy modeling: 
    • Core-valence separation (CVS) scheme for ROCIS, XCIS, and QROCIS: Calculate accurate core-level spectra of open-shell systems
      Avik Ojha, John Herbert
    • Inner-valence projection option for EOM-IP/EE-CCSD solvers: Calculate high-lying excited/ionized states dominated by the removal of an inner-valence electron by using a CVS-like treatment.
      Wojtek Skomorowski
    • New ΔSCF Driver: Run ΔSCF calculations easier and more quickly, with a streamlined, simple interface and new useful tools for analysis of results
      Juanes Arias Martinez
  • Performance improvements and features for large systems:
  • DFT developments:
    • New DFT methods: B97MV-D3s(BJ), B97MV-D4, wB97MV-D4, wB97MV-D3s(BJ), wB97XV-D3s(BJ), wB97XV-D4, Pr2SCAN69-D4, Pr2SCAN50-D4, wPr2SCAN50-D4, revDOD-PBEP86-D4, revDSD-PBEP86-D4, xDSD75-PBEP86-D4, wDSD72-PBEP86-D4, B2NC-PLYP, mPW2-PLYP, mPW2NC-PLYP, SOS0-PBE0-2
    • Support for B97-type functionals in TAO-DFT
      Shaozhi Li, Jeng-Da Chai
    • PBEh-3c and HF-3c Seminumerical Analytic Frequency: Provides similar accuracy and scaling to analytic Hessians. HF-3c especially is good for very efficient geometry optimizations (good accuracy for noncovalent interactions at the cost of minimal-basis Hartree-Fock). Also includes frequencies!
      Avik Ojha, John Herbert
    • Upgrade to DFT-D4
    • Mixed-reference SF-DFT (MR-SF-DFT): Improves accuracy and solves the spin-contamination problem in the original SF-TD-DFT
      Arnab Chakraborty, Zheng Pei, Yihan Shao, Anna Krylov
  • NEO developments:
    • NEO-CC2 method for excited states
      Jonathan Fetherolf, Sharon Hammes-Schiffer
    • NEO-CCSD(T) and NEO-CCSDTeep,epp methods
      Rowan Goudy, Sharon Hammes-Schiffer
    • Frozen core approximation for NEO methods
      Rowan Goudy, Sharon Hammes-Schiffer
    • Geometry optimization with finite-difference gradients for NEO-CC
      Rowan Goudy, Sharon Hammes-Schiffer

For a full list of new features and bugfixes, please review the official Q-Chem 6.4 release log here.

 

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