**Release log for Q-Chem 5.0**

**5.0.2 Release**

**5.0.2 Release**

**[New features and methods]**

- New density functional: revM06-L

- Analytic evaluation of the nuclear hessian with effective core potentials

- Added support for long-range corrected density functionals in spin-flip TD-DFT nuclear gradient calculations

**[Improvements]**

- Several changes in the SAD guess that improve SCF convergence

- Improved shared-memory parallel performance in DFT frequency calculations

- Reduced disk utilization in coupled cluster and equation of motion jobs

- Improved handling of near-zero eigenvalues in the atomic basis overlap matrix

**[Bugfixes]**

- Resolved an issue that caused incorrect accumulation of the components of the ECP nuclear gradient and numerical ECP nuclear hessian

- Resolved several memory issues with the evaluation of MO integrals and nuclear gradients using CC/EOM

- Resolved memory issue in computing Cholesky decomposition of the integrals in CC/EOM jobs

- Resolved symmetry-related issues in computing Hirshfeld charges for SM12

- Corrected energy printout in dual-basis SCF calculations

**5.0.1 Release**

**5.0.1 Release**

**[New features and methods]**

- Spin-adapted version of SF-TDDFT (Xing Zhang, John M. Herbert)

- DFT-C empirical correction for BSSE (Jonathon Witte, Martin Head-Gordon)

- Simplified calculation of singlet states in the solvent-field of a triplet state using ADC/SSPCM

- Improved memory defaults in CC/EOM computations

- Improved handling of small deviations in orbital symmetry when setting up CC/EOM calculations

- More user-friendly input of $plot section

**[Bugfixes]**

- Resolved an instability forcing standard electronic orientation that lead to small errors in non-orbital-invariant post-HF energies

- Resovled an issue that prevented using reconstructed Cholesky-decomposed two-electron integrals in CC calculations

- Resolved an issue that results in the incorrect analytical gradient of non-equilibrium PCM with post-HF methods

- Resolved issues with running real-time TDDFT computations with long-range-corrected density functionals

- Resolved an issue that results in errors in the IEF-PCM gradient in parallel runs

- Resolved an issue that caused CPCM-CG frequency calculation crashes

- Resolved an issue that prevented reading the $molecule section from a previous calculation if the molecule contains ghost atoms

- Resolved issues with excited-state density plotting

**5.0.0 Release**

**5.0.0 Release**

**[New features and methods]**

-New implementation of effective core potentials

-Analytic gradients for resolution-of-the-identity and Cholesky-decomposed coupled-cluster and equation-of-motion (RI/CD-CC, RI/CD-EOM) theories

-Analytic gradients for the complex-absorbing potential--equation-of-motion (CAP-EOM) method

-Non-adiabatic couplings at the CC and EOM levels of theory

-Self-consistent SS-PCM equilibrium solvation for ADC excited states

-Fast time-dependent density functional theory for the X-Ray absorption spectroscopy in large systems

-Frozen density embedding at the algebraic diagrammatic construction (ADC) level of theory

-Global-density-dependent scheme for optimizing the range-separation parameter in long-range-corrected density functionals

-Vibrational mode localization

-RAS(S,2h,2p)-SF method

-New propagators for real-time TDDFT

-Poisson equation boundary conditions

-Derivative couplings via ab-initio Frenkel-Davydov exciton model

-Non-Equilibrium Greens function (NEGF) method for Molecular Junction

-Compute XES and RIXS spectra from Kohn-Sham DFT

-Random search structure optimisation for molecular/atomic clusters

-Computation of dipoles and polarizabilities using the finite difference method

-Solvent-excluded surface for PCM

-Non-orthogonal CI-MP2

-New exchange-correlation functionals optB88, PBE-GX

-Local XC: HLE16, KT1, KT2, KT3

-Hybrid XC: CAM-QTP00, CAM-QTP01, rCAM-B3LYP, WP04, WC04, TPSS0

-Double hybrid XC: DSD-PBEPBE-D3, DSD-PBEP86-D3, DSD-PBEB95-D3, PTPSS-D3, PWPB95-D3, B2GPPLYP, PBE-QIDH, LS1DH-PBE

-SG-2 and SG-3 integration grids

-D3 corrections

-PBEh-3c gCP "low-cost" method

-Bonded EDA

-Adiabatic EDA

-EDA based on symmetry-adapted perturbation theory (SAPT) + constrained DFT (CDFT)

**[Performance improvements ]**

-Shared-memory parallel occ-RI-K algorithm for energy and gradients

-Improved shared-memory parallel RI-MP2 algorithm

-Improved shared-memory parallel algorithm for CC and EOM analytic gradients

-Improved shared-memory parallel CCSD(T) algorithm

-Shared-memory parallel implementation of constrained DFT

-Improved shared-memory parallel performance of analytical frequency calculations

-Improved shared-memory parallel performance and memory management in CIS and TDDFT calculations

**[Bugfixes]**

-Resolved numerical issues that caused spurious negative eigenvalues of the AO overlap matrix

-Resolved an issue that prevented user-specified van-der-Waals radii in PCM calculations