Give examples of methods used to find approx. answers to the Schrödinger's eqn. of systems too complex to be solved analytically.
The Attempt at a Solution
I understand there are three methods commonly used, those mentioned in the title and a 3rd, perturbation theory (of which i can explain) however variation and hybridisation have me at a loss. I've tried many internet sources and my local physics library has no books available.
From what i understand Variation Theory envolves modifying the wave equations of fundamental systems used to describe a system (fundamental systems being things like the rigid rotor, harmonic oscillator, hydrogen-like atom etc.)
Hybridisation however i have less knowledge of, from the name i imagine its something to do with combining states of atoms/molecules.