A particle of mass in an infinite spherical potential well of radius is described by the Schrödinger equation . The wavefunction is separable in spherical polar coordinates, such that , where is a spherical harmonic, a spherical Bessel function, and is a normalization constant. The boundary condition that at is fulfilled when is the zero of the spherical Bessel function . The quantized energy levels are then given by and are -fold degenerate with . The conventional code is used to label angular momentum states, with representing . Unlike atomic orbitals, the -values are not limited by ; thus one will encounter states designated , etc.