The lattice parameter of the²⁸Si spheres in the determination of the Avogadro constant

Abstract

The Avogadro constant has been determined by atom counting in two enriched 28 Si spheres. Atoms were counted by exploiting their ordered arrangement in the spheres and calculating the ratio between sphere and the unit-cell volumes. This paper describes how the values of the sphere lattice parameters and, consequently, their unit-cell volumes were obtained.