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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…

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4 355 October 8, 2026
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1 195 October 5, 2026
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1 311 September 28, 2026
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0 224 September 24, 2026
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0 307 September 22, 2026
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1 287 September 16, 2026
Dyson orbitals between EOM-IP and EOM-DIP states with a CAP active
Questions
0 298 September 2, 2026
Frequency calculation stalls during CPSCF/CPCM-SWIG Hessian step
Questions
3 317 August 31, 2026
Spherical or Cartesian
Questions
4 352 August 26, 2026
r2scan very slow (not scf but doing extra calculations)
How To
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1 300 August 17, 2026
Q-Chem Webinar 89: M-Chem
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0 309 August 13, 2026
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1 362 August 5, 2026
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Questions
3 893 August 10, 2026
BSSE error input file
Questions
5 924 August 10, 2026
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0 373 August 5, 2026
Webinar 88: What's new in Q-Chem 7
Announcements
0 379 July 28, 2026
CDFT-CI convergence issue
Questions
1 416 July 26, 2026
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Questions
1 433 July 24, 2026
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1 1074 March 12, 2023
Some doubt regarding CAP onset
Questions
3 457 July 6, 2026
Calculation of transition density matrices between CVS-ADC(2)-x excited states
Questions
0 381 June 30, 2026