Connection to Ewald Sum
Surface charges on dielectric produce a non-negligible electric field throughout
- Local regions inside dielectric feel this field, even though they have no polarization charge
- Surface charges arise when the system has uniform polarization
dipole moment per unit volume
In simulation of polar systems, at any instant the system will exhibit an instantaneous dipole
- This dipole is replicated to infinity
- But in principle it stops at some surface
- Should the resulting field influence the simulated system?
- The boundary conditions at infinity are relevant!
k = 0 term corresponds to this effect