New modified RungeKuttaNystrm methods for the numerical integration of the Schrdinger equation
In this work we construct new RungeKuttaNystrm methods especially designed to integrate exactly the test equation y?=?w2y y ? = ? w 2 y . We modify two existing methods: the RungeKuttaNystrm methods of fifth and sixth order. We apply the new methods to the computation of the eigenvalues of the Schrdinger equation with different potentials such as the harmonic oscillator, the doubly anharmonic oscillator and the exponential potential.
rungekuttanystrm methods schrdinger equation exponential fitting