Density comparison of isotopically enriched silicon single crystals by the pressure-of-flotation method

Abstract

An isotopically enriched silicon crystal is recently available for a new determination of the Avogadro constant. Density comparison measurement is presented for enriched ²⁸Si crystals by the pressure-of-flotation (PF) method. Relative density difference for ²⁸Si spheres Avo28-S5 and Avo28-S8 is evaluated to be (2.6±0.9)×10⁻⁸.