Topic Replies Views Activity
Report SCF (HF/DFT) Convergence Issues
Questions

Dear Q-Chem Community, If you have any SCF (HF/DFT) jobs that are time-consuming or are facing convergence difficulties with Q-Chem, please send them to support@q-chem.com with the subject line “SCF Convergence Issue” t…

3 1394 November 22, 2024
Failure in Frequency job
Questions
3 20 April 24, 2026
Webinar 87: Improvements in the OO-DFT user interface
Webinars
0 21 April 23, 2026
Facing convergence issue with CDFT geometry optimization
Questions
1 26 April 22, 2026
TDDFT SOC results
Questions
0 27 April 22, 2026
Loading basis set from file?
Questions
1 42 April 22, 2026
Non-adiabatic bimolecular reaction dynamics
Questions
5 110 April 18, 2026
Energy inconsistency with PySCF / adcc
Questions
3 97 April 17, 2026
Facing Imaginary frequency in excited state
Questions
1 67 April 17, 2026
Issue with fragment job submission in Q-Chem 5.0.1 EDA calculations
Questions
3 86 April 13, 2026
Crash with NO_REORIENT
Questions
4 110 April 10, 2026
Facing large number of imaginary frequencies in LRC-wPBE functional
Questions
3 94 April 7, 2026
Error in RI-EA-CC2 calculation
Questions
3 114 April 5, 2026
Issue with BR89
Questions
3 104 April 2, 2026
IRC calculation issue
Questions
2 137 April 1, 2026
NAC calculation
Questions
3 165 March 27, 2026
How to generate FCIDump file
Questions
3 131 March 25, 2026
SCF convergence problem in CDFT-CI calculation
Questions
3 161 March 24, 2026
Strange outcome in RAS-SF calculation
Questions
0 113 March 17, 2026
Speeding up ADC(2) calculations
Questions
2 156 March 17, 2026
Is it possible to print gradients of several excited states?
Questions
3 150 March 14, 2026
Memory and RICIS(D) calculations
Questions
4 140 March 11, 2026
MRSF: differences between Q-Chem and OpenQP
Questions
0 175 March 8, 2026
SOC for unrestricted TDDFT
Questions
3 417 March 6, 2026
Gradient and Hessian using CCSD and EOM-CCSD
Questions
3 169 March 5, 2026
Resolution of identity for CDFT?
Questions
6 203 March 3, 2026
ROHF energy discrepancy between Q-Chem and CFOUR
Questions
4 223 February 28, 2026
Optimal settings for large DFT calculations
Questions
3 552 February 28, 2026
Using FRAGMO with ptSS-PCM and CDFT for Vertical Electron Transfer Calculation
Questions
3 166 February 26, 2026
Geometry Optimization with SS_PCM
Questions
1 196 February 25, 2026