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…

3 419 November 22, 2024
How to do PES of a specific singlet excited state
How To
2 25 June 2, 2025
Optimal settings for large DFT calculations
Questions
0 26 June 1, 2025
Temperature in Vibrationally resolved spectra calculations
Questions
2 34 May 31, 2025
Open Shell MBD forces
Questions
1 28 May 31, 2025
BASIS2 and GPUs - again
Questions
8 57 May 31, 2025
CCSD for core excited electrons
Questions
5 67 May 30, 2025
Too large imaginary frequency
Questions
1 32 May 29, 2025
CPSCF Failure error in Frequency calculations
Questions
3 50 May 27, 2025
SCF convergence problem
Questions
4 74 May 26, 2025
Crash during QMMM calculations
Questions
6 71 May 25, 2025
Getting whole set of OPDMs and Dyson orbitals
How To
2 58 May 23, 2025
How to generate NTO cube files for EOM-EE calculations?
How To
4 674 May 18, 2025
How to get NTO pictures or plots of molecules
Questions
1 39 May 18, 2025
Restart crashed SCF calculation
Questions
3 58 May 16, 2025
How to use ccsd to get analytical polarizability
How To
3 100 May 14, 2025
Simulating spectra with implicit solvent models
Questions
1 68 May 13, 2025
Error in SCF convergance
Questions
1 56 May 11, 2025
Ask for temeparture command
Questions
1 49 May 11, 2025
Mixed basis give me this error code
Questions
1 61 May 10, 2025
CCSD(T) Harmonic and Anharmonic Frequencies
Questions
1 81 May 8, 2025
Issue Submitting Job to Q-Chem Server via IQmol
Questions
4 78 May 5, 2025
B3LYP+XDM and RI problem
Questions
2 73 May 4, 2025
TMI of strongly coupled excited states
Questions
1 63 May 3, 2025
Using EFP to model Water/Ionic Liquid mixture
Questions
0 68 May 1, 2025
Distributed Gradients for Anharmonic Frequencies, VPT2 input questions
Questions
0 67 May 1, 2025
Simulating Vibronic and Resonance Raman Spectroscopy Using the VIBRONIC module of Q-Chem
How To
9 2294 April 30, 2025
Freezeing molecular structure in MM calculations
Questions
1 69 April 30, 2025
Ab Initio molecular dynamics with fixed QM potential
Questions
1 65 April 29, 2025
BSSE error input file
Questions
3 99 April 29, 2025