Although the bound state energies and wavefunctions of a two-dimensional harmonic oscillator are trivially derived from those of the one-dimensional case, we use the example of the harmonic oscillator to illustrate the performance of the Fourier grid Hamiltonian algorithm as implemented in WavePacket.
For illustration we consider a two-dimensional harmonic oscillator with slightly different force constants along the two spatial coordinates. Here we chose force constants of 0.81 and 1.00 which result in frequencies of 0.9 and 1.0 for vibrations along R1 and R2, respectively (for unit masses).