Bragg Formulation and von Laue Formulation

Both of these approaches explain the reflected x-ray from a lattice, so the structure of the lattice can be predicted. The Bragg Formulation has two main assumptions: 1. The x-ray will reflects "perfectly" by ions in only one lattice plane. 2. The reflected beams interfere constructively always. The von Laue Formulation is considered more sophisticated because it can explain the reflection of the rays without the need of planes grouping. But it does agree with Bragg in the second assumption.