1.3.2 New Features in Q-Chem 6.2

Changes to keywords and default behavior:

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  Rename keyword TdNonEq to Td_CEq_NonEq to clarify that it is specifically for applying the constrained equilibrium principle in nonequilibrium solvation (Haisheng Ren)

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  SYM_IGNORE keyword is now correctly set to TRUE if NO_REORIENT=TRUE was requested (John Herbert)

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  Increased default printing threshold (CIS_AMPL_PRINT) to 15 for AIMD jobs with state analysis (Goran Giudetti, Anna I. Krylov)

General features and improvements:

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  Increase maximum number of atoms and basis functions for NBO to 300 atoms and 3000 basis functions (John Herbert)

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  Improve documentation for NBO (John Herbert)

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  Re-enabled increasing orbital printing precision via ORBITAL_ENERGY_PREC (John Herbert)

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  Resolved issues with:

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    Incorrect "current job invalid" failure when JOBTYPE = RAND and JOBTYPE = BH

Density functional theory and self-consistent field:

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  Print properties in TAO-reference systems (Shaozhi Li, Jeng-Da Chai)

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  Resolved issues with:

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    Fix typo in printing of wGDD tuning parameter (John Herbert)

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    Incorrect result for M06-2X analytic second derivative calculation for unrestricted systems

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    Incorrect result for CIS/TDDFT frequency calculation when NSEG > 1

Correlated methods:

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  Resolved issues with:

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    Orbital decomposition in MO basis erroneously proceeds for zero Dyson orbital norm in CCMAN2

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    Failure of CASSCF geometry optimization jobs with libopt3

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    Failure when using a SAD guess for unpaired electron systems in RASCI1

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    Incorrect results for EOM-EE-CCSD expectation-value polarizability code with right response vectors

Fragment and energy decomposition analysis improvements:

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  SCF_CONVERGENCE for fragments in EDA calculations is now set to be the same as the parent job (Yuezhi Mao)

Changes to default behavior:

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  Set correct default values of EDA_COVP_THRESH for COVP and NOCV thresholds, when not set by user (Yuezhi Mao)

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  Corrected the list of optical dielectric constants defined for SolventName (John Herbert)

General features and improvements:

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  Enable use of $=$ signs in several input sections (John Herbert)

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  Enable higher initial angle to be called first in PES scan (Andrew Gilbert)

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  Enable NTO analysis for Fast XAS TDDFT calculations

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  Resolved issues with:

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    Failure of some large CPSCF and Hessian jobs due to FileMan error

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    Geometry optimizer reports failure to converge on the maximum cycle permitted by GEOM_OPT_MAX_CYCLES, even if that cycle has converged

Density functional theory and self-consistent field:

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  Enable generation of CAP-HF electron density cube files (Charlotte Titeca, Thomas Jagau)

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  TDDFT analytic frequency OpenMP parallel performance improvements

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  Resolved issues with:

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    Orbital parameterization bug in XES with DFT/CIS (Aniket Mandal, John Herbert)

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    Real- and complex-valued molecular orbital cube files in CAP-HF calculations overwrote one another (Charlotte Titeca, Thomas Jagau)

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    Bug in diabatic state energies for NEO-MSDFT for range-separated (electronic) functionals (Joseph Dickinson, Eno Paenurk, Sharon Hammes-Schiffer)

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    SGM failure for quartet core ion ROHF optimization in 1C-NOCIS (Juanes Arias-Martinez, Martin Head-Gordon)

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    Scaling bug in RI-JK nuclear gradient

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    Integer overflow bug

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    Thread-safety bug in libqints-based multipole and ECP

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    Vibrational analysis in libopt3 ignores multipole field

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    Vibrational analysis in libopt3 crashes for numerical gradient

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    Failure of TDDFT derivative coupling jobs with external charges

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    Incorrect D4 dispersion correction for charged species

Correlated methods:

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  Enable setting EOM-CCSD(fT) method

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  Added error-catching to ensure user-requested states in XOPT/MECP are consistent with requested CCSD/EOM-CCSD states

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  Resolved issues with:

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    Calling CCSD(dT) (unimplemented) would erroneously perform CCSD(fT)

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    Overwriting of Molden files for natural Auger orbitals in resonant Auger decay calculations (Nayanthara Karippara Jayadev, Anna Krylov)

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    State following code crash in CIS calculations (Justin Talbot, Juanes Arias-Martinez)

Molecular dynamics, non-adiabatic dynamics, embedding, and solvation improvements:

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  Resolved issues with:

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    Miscounting of frozen-core orbitals in post-SCF QM/MM calculations using default settings

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    Update total energy print in gen_scfman jobs to include all solvent terms (Yuezhi Mao)

Fragment and energy decomposition analysis improvements:

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  Enable the closed-shell fragments to be frozen in the polarization calculation for fragment spin alignment in EDA2 (Yuezhi Mao)

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  Add print for combined alpha and beta result for unrestricted PolA and CTA (Yuezhi Mao)

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  Simplify the print-out section of ALMO-EDA with implicit solvent models (Yuezhi Mao)

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  Disable orthogonal frozen decomposition when external charges are present (Yuezhi Mao)

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  Resolved issues with:

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    Incorrect print about iterative ALMO-TDA memory requirement (Yuezhi Mao)

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    Energy component analysis for SRC functionals (Felix Plasser)

Miscellaneous:

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  Updated text of Q-Chem license documentation

Changes to default behavior:

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  Set POINT_GROUP_SYMMETRY to FALSE for freq jobs reading guess from previous job to avoid reorientation

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  Make NO_REORIENT = 1 and POINT_GROUP_SYMMETRY = 0 the defaults for harmonic confiner jobs

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  Make improved initial guess Hessian the default for optimizations (INITIAL_HESSIAN = MODEL)

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  Enable RI-K virtual orbital correction by default for occ-RI-K frequency jobs

General features and improvements:

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  NEO Multistate DFT (NEO-MSDFT) (Joseph Dickinson, Qi Yu, Sharon Hammes-Schiffer)

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  Added simulation of nuclear-electronic quantum dynamics based on real-time nuclear-electronic orbital (RT-NEO) (Tao E. Li, Mathew Chow, Sharon Hammes-Schiffer)

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  Added support for D3 empirical dispersion correction (energies and gradients) and Effective Core Potential (ECP) (energies and gradients) for NEO approach and RT-NEO methods (Mathew Chow, Sharon Hammes-Schiffer)

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  Constrained NEO (CNEO) for a single NEO center (Eno Paenurk, Sharon Hammes-Schiffer)

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  Addition of SCS-RIMP2 and SOS-OOMP2 to NEO methods (Jonathan Fetherolf, Sharon Hammes-Schiffer)

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  Faster NEO-SCF via simultaneous DIIS optimization (Mathew Chow, Sharon Hammes-Schiffer)

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  Add atomic multipole moment calculation using IAOs (Alexandra McIsaac, Abdulrahman Aldossary, Martin Head-Gordon)

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  Update the list of occasions not allowed for the AUTOSAD -> CORE fallback when atomic jobs fail (Yuezhi Mao)

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  New syntax allowing external electric field to follow a bond (Tarek Scheele, Tim Neudecker)

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  Real-time extension of TAO-DFT (RT-TAO) (Hung-Yi Tsai, Jeng-Da Chai)

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  SCF energy prints now break one-electron terms into kinetic, nuclear attraction and remainder when SCF_FINAL_PRINT is set to TRUE

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  Resolved issues with:

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    Incorrect hydrogen isotope mass when using EPC functionals with NEO (Mathew Chow, Zhen (Coraline) Tao, Sharon Hammes-Schiffer)

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    NEO Hessian implementation for range-separated functionals (Eno Paenurk and Sharon Hammes-Schiffer)

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    Failure of the READ_REAL guess of complex RHF (Yuezhi Mao)

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    Libopt3 misclassification of structure type for near-zero eigenvalues

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    “SVD Failed" invalid step error in rare geometry optimization cases

Density functional theory and self-consistent field:

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  Implemented DFT/CIS, including a new parameterization for X-ray spectroscopy (Aniket Mandal, John Herbert)

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  Addition of new TZVP basis set for DFT/CIS to QCAUX (Aniket Mandal, John Herbert)

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  Implemented suppression of open-shell mixing for ROKS calculations (Juanes Arias-Martinez, Martin Head-Gordon)

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  Enable negative s8 values for Grimme’s D4 dispersion correction

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  Dipole filtering for restricted and unrestricted TDKS (Avik Kumar Ojha, John Herbert)

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  Print spatial overlaps of orbitals (intermediate overlaps for occ/virt pairs) (John Herbert)

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  Make virtual orbital correction after SCF convergence optional for occ-RI-K

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  Enable MakeMeSAD for GEN_SCFMAN

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  Add SAD guesses for cc-pV6Z and aug-cc-pV6Z

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  Disable AUTOSAD guess for CDFT-CI (John Herbert)

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  Disable NTOs for RPA (John Herbert)

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  Resolved issues with:

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    Job control through FDIFF_DER for anharmonic frequency calculations (Yuezhi Mao)

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    Anharmonic frequency calculation failure with DFT (Yuezhi Mao)

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    Restart initialization for unrestricted TDKS (Hung-Yi Tsai, Jeng-Da Chai)

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    Bug in RI related to basis sets that use multishells (note that this does not affect most RI calculations, unless an auxiliary multishell basis is used)

Correlated methods:

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  Added hyperfine coupling code to calculate couplings between singlet/triplet excited CIS states (Samuel May, Joseph Subotnik)

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  Generalization of 1C-NOCIS to two-electron open-shell singlets (Juanes Arias-Martinez, Hamlin Wu, Martin Head-Gordon)

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  Implemented the ACP-EOMIP-CCSD method to compute partial Auger decay widths (Florian Matz, Thomas Jagau)

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  Built-in implementation of calculations of x-secs and pads using Dyson orbitals (Madhubani Mukherjee, Sarai Folkestad, Anna Krylov)

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  Natural Auger Orbitals for Auger decay, ICD, and related processes for CVS-EOM methods (Nayanthara K. Jayadev, Anna I. Krylov)

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  Added BW-s2 method (Kevin Carter-Fenk, Martin Head-Gordon)

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  Stochastic resolution of identity to CC2 (sRI-CC2) for excited state energy calculations (Chongxiao Zhao, Wenjie Dou, Joonho Lee)

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  EOM-CCSDT for EE and SF states (Prashant Uday Manohar, Manisha)

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  Resolved issues with:

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    Legacy RI-MP2 code crashes when MEM_STATIC value is too large (Yuezhi Mao)

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    Error in calculation of the separable part of the one-particle density matrix with CCSD (Yongbin Kim, Madhubani Mukherjee, Anna Krylov)

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    Overwriting of Molden files for natural Auger orbitals in resonant Auger decay calculations (Nayanthara Karippara Jayadev, Anna Krylov)

Molecular dynamics, non-adiabatic dynamics, embedding, and solvation improvements:

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  External/embedded potential read (Huseyin Aksu, Barry Dunietz)

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  Turn on PCM at the first SCF iteration when SCF_GUESS = READ, allowing faster convergence (Yuezhi Mao)

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  Turn on PCM at the first SCF iteration in the 2nd geom opt cycle for FRAGMO and AUTOSAD (Yuezhi Mao)

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  Clarified ambiguous output for COSMO (John Herbert)

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  Added analytic X-HCFF Hessian (Rahel Weiss, Felix Zeller, AG Neudecker)

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  Resolved issues with:

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    Out-of-bound access error for SMX with ghost atoms

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    Undesirable behavior of SOLVENT_METHOD = TRUE invoking Kirkwood model (John Herbert)

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    Add missing qarchive files for QM/MM calculations (Xiaoliang Pan, Yihan Shao)

Fragment and energy decomposition analysis improvements:

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  Add additional printout for libwfa regarding ionic/covalent states (Felix Plasser)

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  Resolved issues with:

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    Occasional crash in non-perturbative CTA (Yuezhi Mao)

Post-processing features:

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  Calculations of g-tensors using ezMagnet (ref: https://doi.org/10.1021/acs.jpca.3c04134)