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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…

3 1540 November 22, 2024
Calculation of transition density matrices between CVS-ADC(2)-x excited states
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Unexpected Energy Ordering in TDDFT Nonequilibrium PCM
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Amber force field generation
Questions
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What sort of SCF calculations are supported with external fields?
Questions
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Questions
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ALMO-EDA/COVP SCF Convergence Failure for Open-Shell Anion Radical System
Questions
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Questions
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Questions
1 137 May 29, 2026
Simulating Vibronic and Resonance Raman Spectroscopy Using the VIBRONIC module of Q-Chem
How To
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Questions
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Restarting finite difference frequency jobs
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“ADC(3) singlet and triplet excited states with PCM – input and disk quota issues”
Questions
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Questions
3 247 May 13, 2026
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How To
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New basis set - excited states of Argon
Questions
3 265 May 5, 2026
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Questions
6 239 May 4, 2026
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Questions
3 318 May 3, 2026
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Questions
1 208 May 1, 2026
TDDFT SOC results
Questions
3 329 April 28, 2026
Failure in Frequency job
Questions
3 248 April 24, 2026
Webinar 87: Improvements in the OO-DFT user interface
Webinars
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Facing convergence issue with CDFT geometry optimization
Questions
1 230 April 22, 2026
Loading basis set from file?
Questions
1 223 April 22, 2026
Non-adiabatic bimolecular reaction dynamics
Questions
5 331 April 18, 2026
Energy inconsistency with PySCF / adcc
Questions
3 330 April 17, 2026