lines of tension within a nanostructure
Just Got Here
7:39:08 AM PDT - Mon, Sep 12th 2016
Dear NWChem users and developers,

After a full geometry optimization with the tight convergence criteria I get all forces components on atoms as "0.000000" for most atoms since the actual figures are smaller than allowed by the number of decimal places that NWChem uses to print the output file.

I know all gradients/forces are below the maximum gradient specified for the tight convergence and so they are all very small, but they are not expected to be equal for my system (which is highly unsymmetrical) and I would like to assess the lines of tension along the nanostructure, which I might do plotting the forces on selected atoms, which are equivalent although not symmetrical to each other.

How could I get NWChem to print forces and/or gradients with an increased number of decimal places?

Thank you in advance!

best regards,

Andre

Forum Regular
11:17:56 AM PDT - Mon, Sep 12th 2016
There is not currently a way to change the precision of the gradient output. Two alternatives to modifying the source that I can think of are either using the python interface to NWChem (http://nwchemgit.github.io/index.php/Release66:Python), which should give you the gradients as python objects that you could then print to higher precision; or adding

print rtdbvalues

to your input file. This will give you the gradients to full precision, but it will also print a lot of other information to the output file as it dumps the entire contents of the runtime database to the output file.

Just Got Here
12:07:51 PM PDT - Mon, Sep 12th 2016
Quote:Sean Sep 12th 11:17 am
There is not currently a way to change the precision of the gradient output. Two alternatives to modifying the source that I can think of are either using the python interface to NWChem (http://nwchemgit.github.io/index.php/Release66:Python), which should give you the gradients as python objects that you could then print to higher precision; or adding

print rtdbvalues

to your input file. This will give you the gradients to full precision, but it will also print a lot of other information to the output file as it dumps the entire contents of the runtime database to the output file.


Thank you, Sean!
I'll try the print command, should work for my needs.
best
Andre


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