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jochym / qe-doc

Docs and examples for Quantum-Espresso
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Problem With the Calculation of Heat Capacity. #3

Open lim520 opened 10 years ago

lim520 commented 10 years ago

Dear Dr Jochym

I went through the example provided in your tutorials for Lattice dynamics and found that the graph that plotted the Cv Vs Temp is having different values from that reported in the Literature. The graph that we are getting from the Lattice dynamics calculation is giving results with a multiplication factor of e20 ( which is the same when i am trying to redo the same calculation). But the calculations that you provided earlier was correct and was similar to that reported in literature.

Can you please guide to solve this issue.

please compare these two graph

http://nbviewer.ipython.org/github/jochym/qe-doc/blob/master/Lattice_dynamics.ipynb http://nbviewer.ipython.org/url/homepage.usask.ca/~bas627/nipy/html-nipy/Lattice%20dynamics.ipynb?create=1

Regards

Linu

jochym commented 10 years ago

I do not know at the moment what is the reason but I suspect the issue is connected with units used by ASE and QE codes. Both are unfortunately not very consistent with their units. What versions of both packages do you use?

Would you mind adding some comments in your notebook regarding the discrepancy? (lit. sorces or exp. data etc.) It is not clear to me where is the difference.