1.3 Q-Chem Features

1.3.1 New Features in Q-Chem 5.3

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    Changes in default settings:

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      Renamed rem variable ADIABATIC_CTA to VFB_CTA

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      Changed ROHF_DIAG_SPEC default from 0 to 2 for ROHF and set GEN_SCFMAN as default ROSCF engine

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    General improvements:

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      Added support for the jun-cc-pVDZ basis set (K. Carter-Fenk)

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    New features and improvements in the DFT suite:

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      TD-DFT analytic force and frequencies for meta-GGA density functionals

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      Level shifting in DIIS for better SCF convergence in difficult cases (Section 4.5)

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      M06-SX density functional (P. Morgante, R. Peverati)

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      HF-3c method (B. Rana, J. Herbert)

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    New features and improvements in the CC/EOM-CC package:

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      Calculation of RIXS and orbital analysis of RIXS transition moments (K. Nanda, A.I. Krylov; Section 7.10.6.1)

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      New features in the CVS-EOM-CC suite (M. Vidal, S. Coriani)

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      Energies and properties for EOM-DEA-CCSD (S. Gulania, M. Ivanov, A.I. Krylov; Section 7.10.5)

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      Transition properties and <S2> for EOM-DIP-CCSD (S. Gulania, W. Skomorowski, A.I. Krylov)

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      New NLO properties (hyperpolarizabilities) in EOM-CC (K. Nanda, A.I. Krylov)

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      New tools for strongly correlated and magnetic systems: Extention of FNO to open-shell references (P. Pokhilko, A.I. Krylov; Section 7.10.9)

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      Construction of effective Hamiltonians from EOM-CC wavefunctions (P. Pokhilko, A.I. Krylov; Section 13.5)

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      NTO analysis of spin-forbidden transitions (P. Pokhilko, A.I. Krylov; Section 7.10.18.2)

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      Search for special points of complex PES (minima, MECP, and exceptional points) within CAP-EOM-CCSD (Z. Benda, T.-C. Jagau)

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      Voronoi CAP and projected CAP methods (J. Gayvert, K. Bravaya; Section 7.10.7)

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      New tools for computing Auger decay rates and resonance lifetimes by the Feshbach-Dyson method (W. Skomorowski, A.I. Krylov)

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      Stability improvements in EOM-CC (P. Pokhilko, A.I. Krylov)

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    New features and improvements in MP2 methods:

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      Geometry optimization with regularized orbital-optimized second-order Møller-Plesset perturbation theory (κ-OOMP2) (Joonho Lee, M. Head-Gordon; Section 6.6.5)

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    New capabilities for intermolecular interactions:

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      Implementation of the XSAPT+MBD method (K. Carter-Fenk, J. Herbert)

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    QM/MM improvements:

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      L-BFGS algorithm for geometry optimization (B. Rana and J. Herbert)

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      Harmonic confining potentials (S. Dasgupta and J. Herbert)

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    New methods and capabilities:

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      Nuclear-electronic orbital DFT and TD-DFT methods (F. Pavosevic, Zhen Tao, S. Hammes-Schiffer)

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      New module for RAS-SF methods (S. Houck, N. Mayhall)

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      A family of configuration-interaction methods: non-orthogonal configuration interaction singles (NOCIS), static exchange (STEX), and one-center NOCIS (K. Oosterbaan, M. Head-Gordon)

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      Integral screening and resolution-of-the-identity capabilities for complex basis functions (T.-C. Jagau)

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      RI-MP2 method for complex basis functions (M. Hernández Vera, T.-C. Jagau; Section 6.6.8)

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      New method (concentric localization) for truncating the virtual space in projector-based embedding theory (Yuezhi Mao)

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      Square gradient minimization for excited-state orbital optimization (D. Hait, M. Head-Gordon)

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      Resonance Raman spectroscopy simulation (S. Dasgupta, B. Rana, J. Herbert)

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      Population analysis of antibonding orbitals (A. Aldossary)

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      Fragment-based diabatization schemes (Yuezhi Mao)

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      Enabled ghost atoms without basis functions (B. Alam and J. Herbert)

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      Electron localization function (A. Bushra, J. Herbert)

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      New input options for wavefunction analysis (F. Plasser)

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    New features in the BrianQC GPU module:

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      Extended support for GPU accelerated DFT exchange-correlation with support for LDA, GGA, and meta-GGA functionals

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      Partially GPU accelerated DFT frequency calculations