[Wien] Would like to have some guidance from you

[Dr Qi Wen YAO]

Dear professor Blaha and Wien2k users,
 
Thanks to the Wien2k Workshop, now that I can do some proper calculation but since i am new to Wien2k and I would like to have some guidance in my current calculation.

I am doing a supercell (3x3x1) calculation (for publishing quality) to a layered structure perovskite A2BO4 compound. It is of K2NiF2 structure (SG I4/mmm), its resistivity is at around 0.001 Ohm-m at room temp so it is semi-conductive.

Half of the "A" atoms (A atom is Sr in this case, and the B atom is Co) are replace by an Rare Earth atom so the whole supercell is of 90 atoms in size in my struct file. The original unit cell parameters were a=b=3.8 Amstrong and c=12.3 Amstrong.

I am using a PC with 2 core Xeon 2.4GHz, 4G RAM running latest Susie, latest Wien2k and ifort11.

The calculation is Spin Polarized (and not an anti-ferromagnetic as I know that this compound is ferromagnetic), I used 200 k-points for the current calculation. 

The initialization seems working fine (thanks to professor Blaha's guidance in the workshop).

Now it seems that the calculation is a bit too much for this computer - it runs painfully slow and after two days, it only just displays to me two lines: "LAPW0 END" and "LAPW1 END".

I am wondering: for this calculation, can I use less k-points say 50 (as it is a big cell) and the result would still be good enough for paper publishing?

What kind of speed up do I expect if I am to use a 50 k-pints instead of 200 k-points?  

Would you think that a computer with i7 core and 16GB of RAM would be able to run this calculation without too much trouble (I am trying to convince my boss to purchase a new PC for me for WIEN2k)?

Any comments/feedback would be greatly appreciated.

Thank you for your time.

kind regards,
Qiwen

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Dr QiWen YAO

JSPS Fellow
Multifunctional Materials Group
Optical and Electronic Materials Unit
Environment and Energy Materials Research Division

National Institute for Materials Science

1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
Phone: +81-29-851-3354, ext. no. 6482, Fax: +81-29-859-2501

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