The density dependences of a model structure of amorphous iron and a hard-sphere system are investigated at absolute zero temperature. Models (686 particles) are constructed by the static-relaxation method. Pair-correlation functions of the hard spheres depend upon the algorithm of its construction. They are close to the properties of the real filling of the spheres in the static-relaxation method. With increasing density, the height of the first peak in the structure factor decreases slightly in both the systems.