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A new determination of Avogadro's constant N(A) using a direct method gives a result of N(A) = 6.0221363 x 1.0E23/mol. This differs from the most recent CODATA value of 6.0221367 x 1.0E23/mol by only 0.07 ppm, the relative uncertainties being 1.1 ppm and 0.6 ppm, respectively. The value was derived from the determination of the lattice parameter, the density and the molar mass of a silicon single crystal. It will be possible in the future to reduce further the uncertainties of measurement by the procedure described.

Additional information

Authors: SEYFRIED P ET AL., Physikalisch-Technische Bundesanstalt, Braunschweig (DE);DE BIEVRE P ET AL., JRC Geel (BE)
Bibliographic Reference: Article: Zeitschrift für Physik B - Condensed Matter, Vol. 87 (1992) pp. 289-298
Record Number: 199211332 / Last updated on: 1994-11-29
Original language: en
Available languages: en