I calculate an insulator containing 4f electrons. When I set LEPSILON = .TRUE., the OUTCAR gave the negative value for the static dielectric constant. The following is my result:
ε x y z
x 4.75 0 -0.174
y 0 4.902 0
z -0.174 0 5.363
I'm wondering why the dielectric constant would be negative?
And how to define the three directions x,y,z? Do they have relationship with the vectors a,b,c?
Thanks ahead.
<span class='smallblacktext'>[ Edited ]</span>
negative value of the static dielectric constant
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linglin
negative value of the static dielectric constant
Last edited by linglin on Tue Aug 11, 2009 2:36 am, edited 1 time in total.
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wahyu
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negative value of the static dielectric constant
The x,y,z are the cartesian axes.
I have the same experience. for Lu2SiO5 with PAW_PBE and 4f-electrons, all values of dielectric constant are negative??? any update on this?
I have the same experience. for Lu2SiO5 with PAW_PBE and 4f-electrons, all values of dielectric constant are negative??? any update on this?
Last edited by wahyu on Thu Jul 15, 2010 3:12 pm, edited 1 time in total.