Dear Sir,
I am encountering a problem calculating the dipole moment for a periodic 2D system, such as twin-graphene. Using the electron density difference HDF5 file, I have successfully calculated the dipole moment for H₂O, NH₃, and HF, with values that exactly match the literature. However, when applying the same code to the periodic system, such as twin-graphene, it shows an intrinsic dipole moment instead of the expected zero dipole moment