Hello everyone,
My job is to optimize the geometry of a bromobenzene and an acetone at MP2/cc-pVTZ level, the structure has already been optimized at low level, and a fatal error occurred in my output file:
Q-Chem fatal error occurred in module 0, line 459:
MaxKL too small for Path 2. Use more memory.
Q-Chem fatal error occurred in module forms2/ShlPairs.C, line 54:
In ~ShlPairs: s2Ints != 0.
and I have tried to add the keywords
MEM_STATIC = 480
MEM_TOTAL = 8000
for larger memory, but the error still occurred.
Does anyone can give me some suggesttions?
Thanks a lot!
If you can post a full input file I could give better advice, but some things to try are
(1) MP2 is memory/disk intensive, so suggest increasing memory still more, along with AO2MO_DISK
(2) METHOD=RIMP2 is likely considerably faster. In that case, you need to specify the matching auxiliary basis set (AUX_BASIS = RIMP2-CC-PVTZ)
I double both of these suggestions. Increasing memory to MEM_STATIC=1000 solves the problem with conventional MP2 and cc-pVTZ basis, however using RI-MP2 is recommended for performance reasons.
I’m glad that resolved your problem. However, you really should consider RIMP2 as an alternative. Negligible errors for relative energies and considerably faster, better parallel scaling.