[Wien] Deformation of Diamond

[Hui Wang]

Dear wien2k master:
    I am running wien2k09.2 on Suse linux OS, with ifort 11 and mkl 10, inter mpi. 
    Here, there are 3 problem confusing me:
    (1)I wanna calculate the bulk modulus of Diamond. Diamond have cubic sysmetry, and there are 8 atoms in unit cell, 2 atoms in primitive cell. My question is: I wanna calculate the unit cell with 8 atoms, I don't wanna calculate the primitive cell with 2 atoms, because "x sgroup" will automatically change to primitive cell with 2 atoms if I set up a unit cell with 8 atoms, so how can I calculate the unit cell with 8 atoms ?
 
    (2)I wanna calculate the elastic constant such as C11 of Diamond, so I wanna deform the unit cell with 8 atoms in x axes, for instance: lattice constant is a=b=c=3.56 Ang, I wanna calculate the unit cell with 8 atoms when a=3.54, a=3.55, a=3.56, a=3.57, a=3.58 (b=c=3.56 all the time). When I calculate a=3.54, the sgroup will find a new spacegroup "141 (I 41/a m d) [origin choice 2]", and "x sgroup" find:
=====================================   
Bravais lattice: Tetragonal body centred 
  a             b            c
 4.73936977    4.73936977   6.72248100
     alpha         beta         gamma
 90.00000000    90.00000000   90.00000000
=====================================
I think this result is too ridiculus, far away from my requirment. If I don't accept the "x sgroup" result, there are errors when "x symetry" ends. So what shoud I do when I wanna deform Diamond along x axes ?
 
    (3)I used to use vasp to calculate bulk modulus of Diamond, when I use Murnaghan fit formula or Mosrse fit formula to get the bulk modulus, the energy unit is eV and lattice constant is Angstron. Here my questions is: wien2k's energy unit is Ry and lattice constant unit is Bohr, so do I need to convert Ry to eV and Angstron to Bohr when I use Murnaghan fit and Morse fit ? 
 
    I am looking forward to your reply, any help will be appreicated:)
 
Yours sincerely:
Hui 

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