[Wien] Discontinuity in volume optimization curve

[Hernandez, Sarah C]

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
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