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The Si-Route to the Avogadro Constant: Latest Measurements on Natural Silicon; Highly Enriched 28Si Is Next
Published
Author(s)
P De Bievre, S Valkiers, P D. Taylor, P Becker, H Bettin, U Kuetgens, A Nicolaus, H U. Danzebrink, K Fujii, A Waseda, Giovanni Mana, A Peuto, M J. Kenny, A J. Leistner, R Kessel, G Zosi, A Picard, F Spaepen, H Riemann, H S. Peiser
Abstract
New measurements of the molar volume and lattice parameter of natSi, in near-perfect Si crystals, are reported. The present determination confirms the previously published value of the Avogadro constant within the stated uncertainty. all relevant information has been brought together in a Web-based database. Further reduction in uncertainty using natSi is unlikely. Future work will use 99.99 % enriched 28Si. All the measuremtnes are planned and performed within a worldwide, structured collaboration coordinated in the framework of the Working Group on the Avogadro constant of the CIPM-Consultative Committee on Mass and Related Quantities. The goal of this work is to contribute to the redefinition of the kilogram as SI unit for mass. A present best value for the molar volume of Si is released as 12,058 828 4 (18) cm3 and for the Avogadro constant as 6,022 137 7 (12) . 1023 mol-1.
Citation
Conference on Precision Electromagnetic Measurements
Pub Type
Journals
Keywords
Avogadro constant, International System of Units, kilogram, natural silicon, Si, SI unit
Citation
De bievre, P.
, Valkiers, S.
, Taylor, P.
, Becker, P.
, Bettin, H.
, Kuetgens, U.
, Nicolaus, A.
, Danzebrink, H.
, Fujii, K.
, Waseda, A.
, Mana, G.
, Peuto, A.
, Kenny, M.
, Leistner, A.
, Kessel, R.
, Zosi, G.
, Picard, A.
, Spaepen, F.
, Riemann, H.
and Peiser, H.
(2008),
The Si-Route to the Avogadro Constant: Latest Measurements on Natural Silicon; Highly Enriched <sup>28</sup>Si Is Next, Conference on Precision Electromagnetic Measurements
(Accessed October 20, 2025)