The equations of motion (EOM) for the position and gauge invariant crystal momentum are considered for multiband wave packets of Bloch electrons. For a localized packet in a subset of bands well-separated from the rest of the band structure of the crystal. one can construct an effective electromagnetic Hamiltonian with respect to the center of the packet. We show that the EOM can be o... https://www.maximilianopellegrini.com/product-category/anti-rodme-creme/