Optimized basis expansion as an extremely accurate technique for solving time-independent Schr'odinger equation

摘要

We use the optimized trigonometric finite basis method to find energyeigenvalues and eigenfunctions of the time-independent Schrodinger equationwith high accuracy. We apply this method to the quartic anharmonic oscillatorand the harmonic oscillator perturbed by a trigonometric anharmonic term as notexactly solvable cases and obtain the nearly exact solutions.