A generator of hybrid symmetric four-step methods for the numerical solution of the Schrِdinger equation

In this paper a generator of hybrid explicit four-step methods with minimal phase-lag is developed. The methods are of sixth algebraic order and have large intervals of periodicity. The coefficients of the methods are determined in order to have minimal phase-lag. The efficiency of the new methods is showed by their application to the Schrِdinger equation and by their comparison with other well-known methods.