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Efficient use of the clipboard on GaussView


Editing large molecules on a seemingly simple visualizer as GaussView can be a bit daunting. I’m working on a follow up of that project we recently published in JACS but now we require to attach two macrocycles to the organometallic moiety; the only caveat is that this time we don’t have any crystallographic data with which to start. Generating a 3D model of this structure is already hard enough and even when you managed to do it there are many degrees of freedom that in some cases can lead to unrealistic geometries after optimization.

I recently came across a simple way to edit a large complicated molecule by optimizing the fragments separately and then joining them in a new molecule by using the clipboard. This rather simple method, that I for one had never exploited has just saved me a few good hours.

Copy a molecule (CTRL+C) and it will go to the clipboard as a molecular fragment for which you can define a new hot atom and thus bind it to the other fragment as you would with the regular builder. I strongly suggest to use a “New Molecule Group” instead of editing over an existing molecule. Also, if you are using the “paste” button, observe that it has three different options; you may want to use the last one “append to existing molecule” or you will have your fragments in different windows.

And remember, dihedral angles are your best friends.

Some .fchk files wont open in GaussView5.0 (Update)


A couple of weeks ago I posted a solution for a common error regarding .fchk files that will display the error below when opened with GaussView5.0. As I expected, this error has to do with the use of diffuse functions in the basis set and is related to a change of format between Gaussian versions.

CConnectionGFCHK::Parse_GFCHK()
Missing or bad data: Alpha Orbital Energies
Line Number 1234

Although the method described in the previous post works just fine, the following update is a better approach. Due to a change of spelling between G03 and G09 (which has been corrected for G09 but not available for GV versions prior to 5.0.9) one must change “independent” for “independant

To make the change directly from the terminal the following command is needed:

sed -i 's/independent/independant/g' file.fchk

Alternatively you can redirect the output to a new file

sed -e 's/independent/independant/g' file.fchk > newfile.fchk

if you want to keep the old version and work with a new one.

Of course this edition can be performed manually with any text editor available (for example if you work in Windows) but solutions from the terminal always seem easier and a lot more fun to me.

Thanks to Dr. Fernando Cortés for sharing his insight into this issue.

If a .fchk file wont open in GaussView5.0


I’ve found the following error regarding the opening of .fchk files in GaussView5.0.

CConnectionGFCHK::Parse_GFCHK()
Missing or bad data: Alpha Orbital Energies
Line Number 1234

The error is prevented to a first approximation (i.e. it at least will allow GV to open and visualize the file but other issues may arise) by opening the file and modifying the number of basis functions to equal the number of independent functions (which is lower)

FILE HEADER 
FOpt RM062X 6-311++G(d,p) 
Number of atoms I 75
Info1-9 I N= 9
 163 163 0 0 0 110
 2 18 -502
Charge I 0
Multiplicity I 1
Number of electrons I 314
Number of alpha electrons I 157
Number of beta electrons I 157
Number of basis functions I 1199
Number of independent functions I 1199
Number of point charges in /Mol/ I 0
Number of translation vectors I 0
Atomic numbers I N= 75
... ...
... ...

Once both numbers match you can open the file normally and work with it. My guess is this will continue to happen with highly polarized basis sets but I need to run some tests.

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