[Pw_forum] LO-TO splitting in insulators

[Ravi Maranganti]

Hello pwscf users
 I want to find the real space interatomic force constants in an insulator
excluding the contribution from the macroscopic electric field. So i am
calculating the phonon dispersions by specifying .epsil.='false'. And then i
am using q2r.x to find out the real space force constants. Then when i use
matdyn.x with zasr='simple' to calculate the phonon dispersions , i can see
LO-TO splitting at the gamma point. What am i missing? Thanks !
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