Lattice Dynamics: One-Dimensional Crystals

This lecture covers the lattice dynamics of one-dimensional crystals, discussing the displacement of atoms from ideal positions, energy computation using Taylor expansion, force constants matrix, and the response of crystals to atomic perturbations. It also explores the properties of force constants matrices in periodic crystals and the dispersion relation for lattice vibrations. Additionally, it delves into the diatomic spring chain model, analyzing the behavior of two non-equivalent atoms in a lattice unit cell. The lecture concludes with a study of the dispersion relations for different masses in the diatomic spring chain model.