Keywords compatibility XTB & TBLITE

[Viba97]

Describe the bug
Dear community,

I'm trying to use the spin-pol functionality on XTB. I would like to set up for run ONIOM calculation ORCA/XTB. I'm having some convergence problem with my structure and I would like to modify the default parameters, e.g. max-iteration, acc, etemp.

I managed to call tblite inside ORCA (inside xtb) using this ORCA input:

! QM/XTB B97-3c opt miniprint

%qmmm
ActiveAtoms { 45 46 47 57 58 59 60 61 62 66 67 } end
QMAtoms { 45 46 47 57 58 59 60 61 62 66 67 } end
Embedding mechanical
end

%xtb
xtbinputstring "--tblite --spinpol --uhf 1 --iterations 50"
end

%pal
nprocs 48
end

%maxcore 2000

• xyz 0 2
  H 3.13420473904667 -3.38748658681785 -2.07569954278662
  O 3.05344178865368 -2.77387716855178 -1.31715414658506
  H 2.21413546143315 -2.30683674061677 -1.48504378343149
  ........ geometry.....

and the XTB command line input generated by ORCA is the following:

g100_work/IscrB_BEH2O2ND/apps/ORCA/5.0.4/otool_xtb grain_22_oh_S_QM2_XTB.xyz --grad -c 0 -u 1 -P 48 --namespace grain_22_oh_S_QM2 --input grain_22_oh_S_QM2_XTB.input.tmp --acc 1.000000 --tblite --spinpol --uhf 1 --iterations 50

Although in the XTB command line is defined the max-iterations= 50, the calculation reaches 250 SCF cycles and then fail. See grain_22_oh_S_QM2.lastout for the XTB output and grain_22_oh.out for the ORCA output.

I'm not reporting here the test, but I have also tried to give the parameters as input file in the command line (--input filename.inp) but it was NOT succesful. In the same way I tried modifying the .xtbrc .

Is it possible to modify this default parameters?

To Reproduce
Steps to reproduce the behaviour:

The geometry test_oh_small.xyz is the Model Zone created by the ONIOM calculation of ORCA, is an open shell system with an OH interacting with a cluster of water molecules. The calculation which is crashing in ORCA is the Model zone at the XTB level.

1. First test: try to modify the iteration number calling TBLITE inside the command line of XTB ( as it happens during the call in the previous showed ORCA input) with the following command:

xtb test_oh_small.xyz --tblite --iterations 50 --spinpol -u 1 > xtbout_with_tblite_max50.out

The calculation fails because the max number of iterations (250) is reached. Check the output file xtbout_with_tblite_max50.out

2. Second test: try to modify the iteration number calling only XTB with the following command:

xtb test_oh_small.xyz --iterations 50 > xtbout.out

The printed output (xtbout.out) correctly stop the SCF after 50 cycles

3. Third test: try to modify the iteration number calling only TBLITE with the following command:3.

tblite test_oh_small.xyz --iterations 50 > tbliteout.out

The printed output (tblite.out) correctly stop the SCF after 50 cycles

Please provide all input and output file such that we confirm your report.

You can find all the cited files inside the tar: test.zip

Expected behaviour
To be able to modify the default parameters from command line or input file.

.