QCG final geometry optimization at GFN-FF

[moabe84]

Hi everyone,
I'm conducting Solvation Free Energy calculations using QCG for several macromolecules in 100 solvent molecules. I'm curious if it's feasible to employ the GFN-FF method for the Final Geometry Optimization. The default method is GFN2-xTB, which appears to be quite costly for my systems.
Here's my command line for the calculations:
crest mol_1.xyz --qcg water.xyz --nsolv 100 --gfnff --T 60 --gsolv --nclus 5 --mreset 4 --alpb water --nofix

I'm using CREST version 2.12.

Thanks,
Mostafa

[cplett]

Hi Mostafa,
after CREST version 2.12, I updated the source code so that the GFN2-xTB optimization was made optionally if a different method should be used and is then only be performed when using the "--fin_opt_gfn2" flag. This feature is currently only available in the Continous release version or an other version compiled with the current source code.

[moabe84]

Thank you for your reply. If I want to do everything at the GFN-FF level, do I also need to specify the "--enslvl gfnff" keyword:
crest mol_1.xyz --qcg water.xyz --nsolv 100 --gfnff --enslvl gfnff --T 60 --gsolv --nclus 5 --mreset 4 --alpb water --nofix

[moabe84]

I just ran the calculations with the Continous release version (precompiled binaries) using the following command line and it crashed in the "Multilevel Ensemble Optimization" step with this error:

crest pentanol.xyz --qcg benzene.coord --nsolv 25 --gfnff --T 120 --gsolv --nclus 4 --fscal 0.65 --gbsa benzene

input file name : crest_rotamers_0.xyz
output file name : crest_rotamers_1.xyz
reference state Etot : -62.1430257400000
forrtl: severe (174): SIGSEGV, segmentation fault occurred
Image PC Routine Line Source
crest 0000000002659710 Unknown Unknown Unknown
crest 00000000006E1484 cregen_conffile 2510 cregen.f90
crest 00000000006C01EC newcregen_ 260 cregen.f90
crest 00000000005AE3A4 confg_chk3_ 913 confscript2_misc.f90
crest 00000000005AE1C8 sort_and_check_ 1052 confscript2_misc.f90
crest 0000000000517B0D crest_multilevel_ 396 search_conformers.f90
crest 0000000000512C61 crest_search_imtd 129 search_conformers.f90
crest 00000000004214E5 qcg_ensemble_ 1029 solvtool.f90
crest 0000000000406350 crest_solvtool_ 102 solvtool.f90
crest 00000000004041F8 MAIN__ 262 crest_main.f90
crest 000000000040336D Unknown Unknown Unknown
crest 000000000265B9E0 Unknown Unknown Unknown
crest 000000000040324E Unknown Unknown Unknown_