  The general and practical inversion of diffraction data-producing a computer
model correctly representing the material explored - is an important unsolved
problem for disordered materials. Such modeling should proceed by using our
full knowledge base, both from experiment and theory. In this paper, we
describe a robust method to jointly exploit the power of ab initio atomistic
simulation along with the information carried by diffraction data. The method
is applied to two very different systems: amorphous silicon and two
compositions of a solid electrolyte memory material silver-doped GeSe3 . The
technique is easy to implement, is faster and yields results much improved over
conventional simulation methods for the materials explored. By direct
calculation, we show that the method works for both poor and excellent glass
forming materials. It offers a means to add a priori information in first
principles modeling of materials, and represents a significant step toward the
computational design of non-crystalline materials using accurate interatomic
interactions and experimental information.
