[Pw_forum] V - cohesive energy

[Rafael Julian Gonzalez Hernandez]

Hi,

I am calculating cohesive energy for V in bcc structure. The electronic configuration for the V isolated atom is  [Ar] 3d3 4s2.

1) I found for V isolated atom:
  
!    total energy        = -27.27735288 Ry
     total magnetization = 5.00 Bohr mag/cell
and, 
     cohesive energy     = 5.28  (5.31 exp.)

However, should I find a total magnetization = 3 in the isolated atom?

2) With the restriction (tot_magnetization=3) in my input file. I found:

!    total energy        = -27.22435471 Ry
     total magnetization = 3.00 Bohr mag/cell
and,
     cohesive energy     = 6.00  (5.31 exp.)

why is this big difference in cohesive energy?

Rafael J. Gonzalez

====================================================
Rafael Julian Gonzalez    Tel:+57(1)3165000
Department of Physics
Universidad Nacional de Colombia    
email: rgonzalezh at unal.edu.co
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