From: Joel Subach (
Date: Tue Feb 20 2024 - 02:01:03 CST

Hello Pawel thank you for your kind update:).

The ffTK Tutorial indicates that the .chk file for Guassian must be used
for this input which is a binary file analogous to the ORCA generated
binary .gbw file
(according to Git-Hub), whereas the Gaussian .log file is analogous to the
ORCA output.out file which are both non-binary and analogous. And
completion of the ffTK Tutorial was generated via inputting the Gaussian
generated .chk file Please see a paste below in bold of this excerpt from
the tutorial:

*5.1 Characterizing Distortions in Molecular Geometry *

*The target data for fitting bonds and angles involves computing the
Hessian at MP2/6-31G* level of theory, in compliance with CGenFF. This
calculation requires data computed as part of the geometry optimization
performed in section 3. During the course of this previous calculation,
Gaussian output a special file called a checkpoint file (CHK), which is
required as input for the current Hessian calculation. The setup for
computing the Hessian is relatively straightforward from the Calc. Bonded
tab. *

*1 Select the Calc. Bonded tab of the ffTK GUI. *

*2 Use the provided file dialogs to specify the following inputs: *

*PSF: 3-chargeOpt/ETOH.1.psf *
*PDB: 2-geomOpt/ETOH.1.pdb *
*CHK: 2-geomOpt/ETOH.geomOpt.chk *
*Output GAU: 4-baOpt/ETOH.hess.gau*

Also I had tried inputting the ORCA generated output.out file in lieu of
the ORCA generated .gbw file regardless, and did generate the.inp file to
be input into ORCA, however, am generating the below error in bold upon
this ORCA subsequent execution:

*(base) Joels-MacBook-Air:4-baOpt joelsubach$ orca 14C.hess.inp >
output.out[file orca_mp2/mp2ao.cpp, line 1158]: ... Aborting the
run[file orca_main/maingopt.cpp, line 1229]: ORCA finished with an error in
the energy calculation*

Hopefully this error is aside from being an incorrect output.out file being
input (maybe you are correct and using ORCA requires this file, the authors
did not respond
back to this inquiry). Accordingly, are you savvy if this is an error that
can be amended i.e. that the output.out file in this case is the correct

Thanks if you know:),
Joel 🚀

On Tue, Feb 20, 2024 at 8:32 AM Paweł Kędzierski <> wrote:

> Dear Joel,
> W dniu 19.02.2024 o 21:08, Joel Subach pisze:
> > Anyone Completed ffTK Calc Bonded Tab using the ORCA generated .gbw
> > file instead of the Gaussian generated .chk
> I wonder why are you using the .gbw file. I do not think it contains the
> geometry, "gbw" stands for "gaussian basis wavefunction", it's the file
> with optimized molecular orbitals, useful in cases when the wavefunction
> itself is of interest.
> > Opt.Geom CHK/OUT file: 2-geomOpt/ETOH.geomOpt.gbw
> As the entry is named, I think it is intended to be used with .chk from
> Gaussian or the output file .out from ORCA.
> With regards,
> Paweł