[Pw_forum] Pseudopotential combination

[Elliot Menkah]

Hello Everyone,

I'm making an adsorption study of carbon monoxide(CO) on pure nickel(Ni) 
surfaces.
I use the pseudopotential Ni.pbe-nd-rrkjus.UPF to optimized the pure 
nickel system.
Is it wrong to use C.pbe-van_ak.UPF for carbon and O.pbe-van_ak.UPF for 
the oxygen rather than using C.pbe-rrkjus.UPF and O.pbe-rrkjus.UPF
When I use the *pbe-van_ak.UPF* to optimize the CO separately, I get an 
energy of *-75.5429425135* Ry whereas *pbe-rrkjus.UPF* gives me an 
energy of *-75.1901795049* Ry.

In consideration of the energetics and stability, I want to go in for 
the pbe-van_ak.UPF for the system of CO on Ni surface. Is it wrong please?


Kind Regards,

Elliot

-- 
Elliot Sarpong Menkah
Graduate Student - Computational Chemistry / Computational Material Science.
Theoretical and Computational Chemistry
Dept. of Chemistry
Kwame Nkrumah University of Science and Technology (KNUST),
Private Mail Bag,
Kumasi,
Ghana.
Mobile:+233-243-055-717,+233-202-929-058


Alt. Email: elliotsmenkah at gmail.com
                 elliotsmenkah at hotmail.com

webpage: http://archive.knust.edu.gh/pages/sections.php?siteid=chemistry&mid=806&sid=2754

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20140517/9499308d/attachment.html>