The Bloch Model posits that the wavefunction of an electron in a periodic potential can be expressed as the product of a plane wave and a function with the same periodicity as the crystal lattice. This wavefunction is known as a Bloch Function. Mathematically, it can be written as:
ψ_k(r) = e^(i k·r) u_k(r)
where ψ_k(r) is the Bloch Function, k is the wavevector, r is the position, and u_k(r) is a periodic function with the same periodicity as the lattice.
