where the distance vectors rWC i = r WC i r 0 and Ri = R ir 0 are implemented with PBCs and r 0 is a reference point, for example, the center of mass. R i and Z i indicate the atomic positions and charges, respectively. Equation ( ) yields the total dipole moments of the supercell. As for the Berry phase dipole moments, "jumps" of µ µ µ MLWF during the AIMD are possible, which are again corrected by adding/subtracting multiples of a α + b α + c α .