Title :
The determination of the Avogadro constant-not simply a metrological problem
Author_Institution :
Phys. Tech. Bundesanstalt, Braunschweig, Germany
Abstract :
Summary form only given, as follows. A new round in the determination of the Avogadro constant is under way at PTB and at other national metrological institutes as a step towards an alternative definition of the SI unit of mass. The required measurements of the relevant crystal data are currently hampered by an (unexpected and not yet total identified) imperfection of the crystal lattice.
Keywords :
constants; density measurement; lattice constants; mass measurement; silicon; units (measurement); voids (solid); Avogadro constant determination; PTB comparison measurements; SI unit of mass; Si; alternative definition; crystal data measurements; density; interatomic distance; invariant quantity; kilogram realisation; lattice imperfection; lattice parameter; metrological problem; molar volume; vacancy concentration; voids; Atomic measurements; Crystals; Current measurement; Impurities; Microscopy; Prototypes; Temperature; Volume measurement;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 1998 Conference on
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-5018-9
DOI :
10.1109/CPEM.1998.700001
