Non-Axisymmetric Needle Crystals
•Unfortunately, there is no exact generalization of the Horvay- Cahn 2-fold solution to the 4-fold case.
•Instead, we perform an expansion for the 4-fold correction, valid for small-amplitude perturbations to a parabola of revolution.
•Horvay-Cahn solution is written in an ellipsoidal coordinate system. We transform the solution to paraboloidal coordinates, and expand for small eccentricity to find the expansion for a 2-fold solution in paraboloidal coordinates.
•We then generalize the 2-fold solution to the n-fold case (n = 3,4) in paraboloidal coordinates .