1.3 Q-Chem Features

1.3.5 New Features in Q-Chem 4.3

  • Analytic derivative couplings (i.e., non-adiabatic couplings) between electronic states computed at the CIS, spin-flip CIS, TDDFT, and spin-flip TDDFT levels (S. Fatehi, Q. Ou, J. E. Subotnik, X. Zhang, and J. M. Herbert; Section 10.6).

  • A third-generation (“+D3”) dispersion potential for XSAPT (K. U. Lao and J. M. Herbert; Section 13.13).

  • Non-equilibrium PCM for computing vertical excitation energies (at the TDDFT level) and ionization energies in solution (Z.-Q. You and J. M. Herbert; Section 12.2.2.3).

  • Spin-orbit couplings between electronic states for CC and EOM-CC wave functions (E. Epifanovsky, J. Gauss, and A. I. Krylov; Section 7.8.18.2).

  • PARI-K method for evaluation of exact exchange, which affords dramatic speed-ups for triple-ζ and larger basis sets in hybrid DFT calculations (S. Manzer and M. Head-Gordon).

  • Transition moments and cross sections for two-photon absorption using EOM-CC wave functions (K. Nanda and A. I. Krylov; Section 7.8.18.1).

  • New excited-state analysis for ADC and CC/EOM-CC methods (M. Wormit; Section 11.2.6).

  • New Dyson orbital code for EOM-IP-CCSD and EOM-EA-CCSD (A. Gunina and A. I. Krylov; Section 7.8.25).

  • Transition moments, state dipole moments, and Dyson orbitals for CAP-EOM-CCSD (T.-C. Jagau and A. I. Krylov; Sections 7.8.7 and 7.8.25).

  • TAO-DFT: Thermally-assisted-occupation density functional theory (J.-D. Chai; Section 5.12).

  • MP2[V], a dual basis method that approximates the MP2 energy (J. Deng and A. Gilbert).

  • Iterative Hirshfeld population analysis for charged systems, and CM5 semi-empirical charge scheme (K. U. Lao and J. M. Herbert; Section 11.2.1).

  • New DFT functionals: (Section 5.3):

    • Long-range corrected functionals with empirical dispersion-: ωM05-D, ωB97X-D3 and ωM06-D3 (Y.-S. Lin, K. Hui, and J.-D. Chai.

    • PBE0_DH and PBE0_2 double-hybrid functionals (K. Hui and J.-D. Chai; Section 5.9).

    • AK13 (K. Hui and J.-D. Chai).

    • LFAs asymptotic correction scheme (P.-T. Fang and J.-D. Chai).

  • LDA/GGA fundamental gap using a frozen-orbital approximation (K. Hui and J.-D. Chai; Section 5.11).