Dear all I calculated imaginary part of dielectric function for a metal cluster with different radius 0.5, 1 and 1.5 nm. As you know in the siesta for open system, supercell should be determined. My results are dependent on size of supercell and with increasing radius of cluster, size of supercell increases and value of dielectric function decreases while I don't expect this behaviour.
What is the unit of permittivity in siesta I think it isn't dimensionless. I appreciate if anyone has the same experience help me to solve this problem. Regards
