Questions

Topic	Replies	Views	Activity
Report SCF (HF/DFT) Convergence Issues 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	1152	November 22, 2024
About the Questions category	0	1071	July 1, 2020
Using SF-TDDFT single-point energies for TS optimized at DFT level	0	2	January 13, 2026
Is it possible to use the NTO-rotated orbitals (for a specific TDDFT state) as the MO set in a subsequent Q-Chem job?	5	94	January 13, 2026
Which value to choose when calculating SOC?	3	10	January 13, 2026
Energy conservation problems during dynamics , bond breaking and forming for collision reaction	1	34	January 11, 2026
Trouble using EOM-CCSD, with frozen core	9	202	January 9, 2026
$reorder_mo not affecting beta orbitals as expected	4	55	January 9, 2026
Conceptual question regarding the applicability of SF-TDDFT method	1	63	January 9, 2026
Error in EDA 2 calculation	2	45	January 9, 2026
ALMO_EDA job failure	1	35	January 9, 2026
Qchem randomly aborting	3	48	January 7, 2026
Normal Modes Question	1	53	January 2, 2026
Facing issue with spin-contamination	1	84	December 29, 2025
Gradient/Force print in cartesian format for each element	1	64	December 28, 2025
License file for 32 cores in a 128 cores computing node	1	67	December 24, 2025
Checking the input file for inconsistencies... Error Debug	3	89	December 23, 2025
Basis set compatibility issue	3	146	December 23, 2025
IEF-PCM for SMD olvation model	1	95	December 18, 2025
Possible issue with linear dependencies in the basis when calculating dynamic polarizabilities	5	140	December 18, 2025
downloading and installing qcIntel version 6402	1	105	December 17, 2025
Discrepancies between RIMP2 polarizabilities with FDIF = 0 and FDIF = 1	1	100	December 12, 2025
Excitation energy transfer between two carotinoids	3	129	December 12, 2025
Machine learned PES	1	156	December 1, 2025
Partial frozen scan	3	160	November 29, 2025
Dipole Moments with MBD dispersion	1	121	November 28, 2025
Correlation consistent basis sets and effective core potentials should be included?	1	195	November 28, 2025
vdW-TS (MBDVDW) vibrational frequencies	15	261	November 27, 2025
neo-scf calculations	1	112	November 25, 2025
aug-cc-pV(n+d)Z basis sets	1	123	November 25, 2025

Report SCF (HF/DFT) Convergence Issues

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…