  Using the exponentially diffuse boundary potential of Green and Lee (1955),
we develop a Mathematica notebook to treat alpha decay by using the complex
energy approach of Preston (1947), as modified by Pierronne and Marquez (1978).
Our approach allows the potential to change slowly from the well depth of the
interior of the nucleus to the top of the Coulomb barrier, rather than the
sudden step of the simple square well used by Pierronne and Marquez. Recent
interest in possible variation in coupling constants such as the strong
coupling alpha_s motivates us to develop this algorithm which can allow
numerical study of the variation of the decay constant of a nucleus such as
U-238 when the depth of the nuclear potential well changes.
