[Wien] AFM calculations

Jian-Xin Zhu jxzhu at lanl.gov
Sun Feb 22 16:20:35 CET 2009


Dear Prof. Blaha,

Thanks for the clarification on the occupation.
Do you have also any advice on my other question?



>>>> 1. The nonmagnetic USb2 has the tetragonal layered
>>>> structure with P4/nmm
>>>> symmetry.
>>>>
>>>> The cell has 6 atoms with lattice constant a, b=a, and c.
>>>> In the AFM
>>>> state, the magnetic cell is doubled with respect to the
>>>> chemical cell.
>>>> Specifically, the lattice constant along the c direction is
>>>> doubled.
>>>>
>>>> When I prepare the USb2.struct_supergroup file of the
>>>> nonmagnetic state,
>>>> should I keep the lattice parameters as the original (i.e.,
>>>> a, b=a, c), or
>>>> take  them to match the magnetic cell (i.e., a, b=a, 2c)?
>>>>
>>>> If I follow the first way, x afminput does not create the
>>>> input file for
>>>> the program CLMCOPY. If I follow the second way by
>>>> specifying the symmetry
>>>> type as P in w2web,
>>>> after running sgroup, it came with a warning of reducing
>>>> the lattice
>>>> constant from 2c to c, essentially going back to the first
>>>> way.
>>>>
>>>> If I insisted to use the primitive type P and specify 12
>>>> inequivalent atoms in the cell, the complaints with
>>>> "incorrect symmetry"
>>>> came out.
>>>>
>>>> So what's the correct way to construct
>>>> USb2.struct_supergroup?


Regards,

Jian-Xin Zhu







On Sun, February 22, 2009 12:50 am, Peter Blaha wrote:
> You can put occupations of 0.5 in both, spin-up and dn!
>
> PS: The new instgen_lapw of WIEN2k09.1 has full support for AFM/NM
> configurations.
> Try instgen_lapw -h   to see all options.
> You can now specify for each atom "spin-up; dn or non-magnetic".
>
>
> Jian-Xin Zhu schrieb:
>> Hello,
>>
>> Maybe I should allow  the 5p states on Sb atoms to be simply polarized.
>>
>> Cheers,
>>
>> Jian-Xin Zhu
>>
>> On Sat, February 21, 2009 9:48 pm, swati chaudhury wrote:
>>> Hello,
>>> your Usb2.inst file will be:
>>>
>>>> U
>>>> Rn 3
>>>> 5, 3,0.0  N      <----
>>>> 5, 3,3.0  N      <----
>>>> 6, 2,1.0  N
>>>> 6, 2,0.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>> U
>>>> Rn 3
>>>> 5, 3,3.0  N      <----
>>>> 5, 3,0.0  N      <----
>>>> 6, 2,0.0  N
>>>> 6, 2,1.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>> U
>>>> Rn 3
>>>> 5, 3,0.0  N      <----
>>>> 5, 3,3.0  N      <----
>>>> 6, 2,1.0  N
>>>> 6, 2,0.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>> U
>>>> Rn 3
>>>> 5, 3,3.0  N     <----
>>>> 5, 3,0.0  N     <----
>>>> 6, 2,0.0  N
>>>> 6, 2,1.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>> total spin-up and spin down moment will be same.
>>> best of luck.
>>> swati
>>> --- On Sun, 22/2/09, Jian-Xin Zhu <jxzhu at lanl.gov> wrote:
>>>
>>>> From: Jian-Xin Zhu <jxzhu at lanl.gov>
>>>> Subject: [Wien] AFM calculations
>>>> To: "A Mailing list for WIEN2k users"
>>>> <wien at zeus.theochem.tuwien.ac.at>
>>>> Date: Sunday, 22 February, 2009, 3:03 AM
>>>> Dear Wien2k users and Prof. Blaha,
>>>>
>>>> I am doing a AFM calculation with s.o. in USb2.
>>>> Several questions for your help:
>>>>
>>>> 1. The nonmagnetic USb2 has the tetragonal layered
>>>> structure with P4/nmm
>>>> symmetry.
>>>>
>>>> The cell has 6 atoms with lattice constant a, b=a, and c.
>>>> In the AFM
>>>> state, the magnetic cell is doubled with respect to the
>>>> chemical cell.
>>>> Specifically, the lattice constant along the c direction is
>>>> doubled.
>>>>
>>>> When I prepare the USb2.struct_supergroup file of the
>>>> nonmagnetic state,
>>>> should I keep the lattice parameters as the original (i.e.,
>>>> a, b=a, c), or
>>>> take  them to match the magnetic cell (i.e., a, b=a, 2c)?
>>>>
>>>> If I follow the first way, x afminput does not create the
>>>> input file for
>>>> the program CLMCOPY. If I follow the second way by
>>>> specifying the symmetry
>>>> type as P in w2web,
>>>> after running sgroup, it came with a warning of reducing
>>>> the lattice
>>>> constant from 2c to c, essentially going back to the first
>>>> way.
>>>>
>>>> If I insisted to use the primitive type P and specify 12
>>>> inequivalent atoms in the cell, the complaints with
>>>> "incorrect symmetry"
>>>> came out.
>>>>
>>>> So what's the correct way to construct
>>>> USb2.struct_supergroup?
>>>>
>>>> 2. I assume the magnetism comes from the 5f state on U by
>>>> flipping the
>>>> corresponding occupation on U in the file of USb2.inst.
>>>>
>>>> U
>>>> Rn 3
>>>> 5, 3,0.0  N      <----
>>>> 5, 3,3.0  N      <----
>>>> 6, 2,1.0  N
>>>> 6, 2,0.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>> U
>>>> Rn 3
>>>> 5, 3,3.0  N      <----
>>>> 5, 3,0.0  N      <----
>>>> 6, 2,1.0  N
>>>> 6, 2,0.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>> U
>>>> Rn 3
>>>> 5, 3,3.0  N      <----
>>>> 5, 3,0.0  N      <----
>>>> 6, 2,1.0  N
>>>> 6, 2,0.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>> U
>>>> Rn 3
>>>> 5, 3,0.0  N     <----
>>>> 5, 3,3.0  N     <----
>>>> 6, 2,1.0  N
>>>> 6, 2,0.0  N
>>>> 7,-1,1.0  N
>>>> 7,-1,1.0  N
>>>>
>>>>
>>>> However, the UG also reminds that we should set a zero
>>>> moment (identical
>>>> spin up and spin down occupations) for all
>>>> "non-magnetic" atoms.
>>>> In my case, the non-magnetic atoms are Sb. However, there
>>>> is
>>>> one spin up  electron on n=5,kappa=1,
>>>> no spin down electron on n=5, kappa=1,
>>>> two spin up electrons on n=5, kappa=-2,
>>>> no spin down electron on n=5, kappa=-2,
>>>> as shown below.
>>>>
>>>> I can split 2 electron on n=5 and kappa=-2 into one with
>>>> spin up and the
>>>> other with spin dn.
>>>> Then what should do with the only one electron on n=5 and
>>>> kappa=1? Can I
>>>> put it as
>>>> 0.5 and 0.5? I don't find a discussion on this
>>>> situation.
>>>>
>>>> Sb
>>>> Kr 5
>>>> 4, 2,2.0  N
>>>> 4, 2,2.0  N
>>>> 4,-3,3.0  N
>>>> 4,-3,3.0  N
>>>> 5,-1,1.0  N
>>>> 5,-1,1.0  N
>>>> 5, 1,1.0  N
>>>> 5, 1,0.0  N
>>>> 5,-2,2.0  N
>>>> 5,-2,0.0  N
>>>>
>>>> ============>
>>>>
>>>> Sb
>>>> Kr 5
>>>> 4, 2,2.0  N
>>>> 4, 2,2.0  N
>>>> 4,-3,3.0  N
>>>> 4,-3,3.0  N
>>>> 5,-1,1.0  N
>>>> 5,-1,1.0  N
>>>> 5, 1,0.5  N      <----?
>>>> 5, 1,0.5  N      <----?
>>>> 5,-2,1.0  N    <----
>>>> 5,-2,1.0  N    <----
>>>>
>>>>
>>>> Thanks you in advance for help.
>>>>
>>>> Jian-Xin Zhu
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Wien mailing list
>>>> Wien at zeus.theochem.tuwien.ac.at
>>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>> _______________________________________________
>>> Wien mailing list
>>> Wien at zeus.theochem.tuwien.ac.at
>>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>>
>>
>>
>> _______________________________________________
>> Wien mailing list
>> Wien at zeus.theochem.tuwien.ac.at
>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>
> --
> -----------------------------------------
> Peter Blaha
> Inst. Materials Chemistry, TU Vienna
> Getreidemarkt 9, A-1060 Vienna, Austria
> Tel: +43-1-5880115671
> Fax: +43-1-5880115698
> email: pblaha at theochem.tuwien.ac.at
> -----------------------------------------
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>





More information about the Wien mailing list