[Pw_forum] fluctuation in SCF energies of CO adsorbed on Pd110

[David Foster]

Dear users

I have prepared an input for interaction between CO and Pd(110). I optimized 3*3*3 supercell of Pd bulk, and then cleaved a 110 surface and constructed a slab. I inserted CO molecule which has been optimized with QE5.0.2 in it. Now, I try to optimize this mixed system (CO+Pd(110)).

My main problem is that in scf I see the fluctuation in energies. My input and output has been attached. In all calculations I used QE5.0.2 and the same USPP. I used PBE DFT in the PP. I used nspin=2 due to the presence of oxygen atom. I introduced start_magnetization for all species. I fixed three bottom layers in the cell. I used ibrav=14 to optimize bulk phase of Pd, and didn't change it in all computation.
I used degauss=0.001RY. In addition I used smearing technique for both bulk and slab.

The run is continuing, but I think finally, I will encounter with problem.

Any idea for rapid convergence and solve the issue in fluctuation energy is appreciated.




Regards

David Foster

Ph.D. Student of Chemistry
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