Did you do a structure optimization (runsp -min ) ???
This is probably mandatory !

> Total energy is 516 meV greater than the previous case.

You mean more negative (or the absolute value is "greater") ?
We usually say the total energy of a more stable configuration is more negative ....

The 5 mB of Co4+ are again an idealization of a purely ionic model. It does not exist in nature.

On 05/12/2016 11:44 AM, Komal Bapna wrote:
Dear Prof. Peter and Laurence,

I am really thankful for your valuable suggestions.

/Prof. Laurence::/
/
/
These are the bond-valence sums, I am getting
Atom   1 equiv  1 Sr         Bond-Valence Sum     2.40    2.58
Atom   2 equiv  1 Co         Bond-Valence Sum     3.03    3.20
Atom   3 equiv  1 O O1       Bond-Valence Sum     2.25    2.39
Atom   4 equiv  1 O O2       Bond-Valence Sum     1.67    1.78

Please tell the two values in each line. Can I now say that these are
the valence state for respective atom. If it is so, why for Co it is not
4!!!!


/Prof. Peter:: /
/
/
I tried to stabilize a "high-spin" state for Co by changing the 0.8 on
spin-dn to 0.2, and the 0.59 to 0.9 in spin-up.
For Co up spin
          0.89437  0.00000  0.00000  0.00000 -0.04204
          0.00000  0.93434  0.00000  0.00000  0.00000
          0.00000  0.00000  0.91726  0.00000  0.00000
          0.00000  0.00000  0.00000  0.93434  0.00000
         -0.04204  0.00000  0.00000  0.00000  0.89437
Total spin moment: 4.57467
For Co dn spin
          0.34200  0.00000  0.00000  0.00000 -0.05202
          0.00000  0.33947  0.00000  0.00000  0.00000
          0.00000  0.00000  0.34654  0.00000  0.00000
          0.00000  0.00000  0.00000  0.33947  0.00000
         -0.05202  0.00000  0.00000  0.00000  0.34200
Total spin moment: 1.70947

Total energy is 516 meV greater than the previous case.
SPIN MAGNETIC MOMENTS OF MIXED CHARGE DENSITY
INTERSTITIAL  =    0.14578
Sr =    0.00800
Co =    2.89880
O1 =    0.23087
O2 =    0.17575
total moment in the CELL  =    3.87383

Looking at the moments, can I say Co is in high spin state, as the
moment is still low than its actual theoretical high spin moment (~5 muB).

Thanks and Regards

On Tue, May 10, 2016 at 5:24 PM, Komal Bapna <komal.ba...@gmail.com
<mailto:komal.ba...@gmail.com>> wrote:

    Dear Prof. Peter
    Thank you for your kind reply..

    The Density matrix for Co up spin is..
              0.84607  0.00000  0.00000  0.00000 -0.08661
              0.00000  0.92206  0.00000  0.00000  0.00000
              0.00000  0.00000  0.59673  0.00000  0.00000
              0.00000  0.00000  0.00000  0.92206  0.00000
             -0.08661  0.00000  0.00000  0.00000  0.84607
    Total electrons: 4.13298
    and Density matrix for Co dn spin is:
              0.20583  0.00000  0.00000  0.00000  0.06263
              0.00000  0.80064  0.00000  0.00000  0.00000
              0.00000  0.00000  0.25923  0.00000  0.00000
              0.00000  0.00000  0.00000  0.80064  0.00000
              0.06263  0.00000  0.00000  0.00000  0.20583
    Total electrons: 2.27217

    This gives me the net spin moment of 1.86 muB on Co.
    I understood by changing the occupancies we can change the spin
    state. Still I am confused whether I can use these occupation
    numbers of electrons in the respective orbitals to find the spin
    state of Co.Here, total number of electrons is 6.4, 1.4 electrons
    higher than the expected value for Co4+ ion. I may consider the
    extra electrons due to the bonding of Co-O bonds. But, I am really
    unable to calculate the spin state from the present configuration.
    Please suggest how to calculate spin state for the given
    configuration, so that I can modify further.

    Thanks and Regards

    On Mon, May 9, 2016 at 3:59 PM, Komal Bapna <komal.ba...@gmail.com
    <mailto:komal.ba...@gmail.com>> wrote:

        Sir,

        Its true that we can not generate "ionic" electron density with 
lstart/dstart. When I tried to modify .inst file according to the Co4+ ionic state, it 
showed error.

        My query is that how can we generate spin state configuration for such 
an ionic state, it spin states for Co and Co4+ are different and accordingly 
the magnetic moments.


        Please suggest.


        Thanks


        On Fri, May 6, 2016 at 3:18 PM, Komal Bapna
        <komal.ba...@gmail.com <mailto:komal.ba...@gmail.com>> wrote:

            Dear Wien users

            I am working on Sr2CoO4. Here I wanted to study the system with 
different spin state configuration of Co4+, which is known to be valence state 
of Co in this system. I could understand how to create:
                (a) High-spin configuration
                (b) Intermediate spin configuration
                (c) Low-spin configuration
            for the given Co atoms in the .inst file as

            Co
            Ar 3
            3, 2,2.0  N
            3, 2,2.0  N
            3,-3,3.0  N
            3,-3,0.0  N
            4,-1,1.0  N
            4,-1,1.0  N   (for HS state)
            and
            Co
            Ar 3
            3, 2,2.0  N
            3, 2,2.0  N
            3,-3,2.0  N
            3,-3,1.0  N
            4,-1,1.0  N
            4,-1,1.0  N  (for IS state)


            But my query is that .inst file takes Co as neutral atom (9
            electrons:3d74s2) and accordingly its spin state. As if Co were in 
4+ state, I would have 5 electrons in 3d state (3d54s0) rather 9 electrons as 
is revealed from .inst file now.

            Please suggest me how to give spin state for Co4+ for this system.


            Thanks



            --
            *Komal*




        --
        *Komal*




    --
    *Komal*




--
*Komal*


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