Eigenvalues and eigenfunctions Atomistics 1 Band theory 1 Eigenvalue problem 1 Frequency-dependent 1 Localised 1 Machinery 1 Maxwell equations 1 Modal analysis 1 Molecular orbitals 1 Molecular polarizabilities 1 Nano scale 1 Nano-meter-scale 1 Nanostructures 1 Non-local effect 1 Optical lattices 1 Optical- 1 Orthonormal 1 Quantum effects 1 Quasinormal mode theories 1 Quasinormal modes 1 Surface response 1 Susceptibility tensors 1 Tensors 1 Topological bands 1 Topological obstructions 1 Topology 1 Translational symmetry 1 Wannier functions 1