[Wien] Discontinuity in volume optimization curve

[Laurence Marks]

Repeating the email won't get a faster response, it is likely to annoy.

Nobody can help you at the moment since nobody has any idea exactly
what you are talking about as you have not provided the data showing a
discontinuity or anything like enough information (k-points, case.in0
values, case.struct file). All they can do is guess, and I for one am
not feeling inspired to do that this afternoon.

On Fri, Aug 10, 2012 at 12:54 PM, Hernandez, Sarah C
<sarahchernandez at mavs.uta.edu> wrote:
>
>
> Hello!
>
>
>
> When I do a volume optimization of keeping the a:b:c ratio fixed (option 1),
> I get a discontinuity in the E vs. V curve.
>
>
>
> I am using a 32 atom supercell with an impurity. My parameters where
> initially at first RMT(1) = 2.5 and RMT(2) = 2.3 and RKmax = 8.0.  I get the
> discontinuity at approximately volume contraction of 6%.  To fix the problem
> I have tried three separate calculations:
>
>
>
> 1)      Increasing the emax value in the *.in1 file from the default value
> of 2.5 to 3.
>
> 2)      Increasing the RKmax to 9.
>
> 3)      Keeping RKmax at 9 and changing the RMT(2) to 2.13.
>
>
>
> All four separate calculations gave me the same discontinuity.  Note atom 2
> radius is about 15% smaller than atom 1 radius and atom 2 is the impurity.
> Any guidance or suggestions will be greatly appreciated.
>
>
>
> Thank you,
>
>
>
> Sarah Hernandez



-- 
Professor Laurence Marks
Department of Materials Science and Engineering
Northwestern University
www.numis.northwestern.edu 1-847-491-3996
"Research is to see what everybody else has seen, and to think what
nobody else has thought"
Albert Szent-Gyorgi