I have a matrix $$D(\veck)=\sum_\vecR\tildeD(\vecR)\cos(\veck\cdot\vecR)$$where $\vecR$ is summed over all atoms positions and $\tildeD$ are 3x3 matrices. $D(k)$ is called the dynamical matrix in solid state physics.
[Most popular] solid state physics solutions manual by ashcroft mermin 3
2ff7e9595c
Comments