Wronskian Approach and the One-dimensional Schrodinger Equation with   Double-well Potential
  A Wronskian determinant approach is suggested to study the energy and the wave function for one-dimensional Schrodinger equation. An integral equation and the corresponding Green's function are constructed. As an example, we employed this approach to study the problem of double-well potential with strong coupling. A series expansion of ground state energy up to the second order approximation of iterative procedure is given. 
Qiu Jian, Ru-Keng Su