The Avogadro Constant

This fundamental physical constant defines the number of atoms or molecules in one mole [Cohen/Cvitas/etal_2007] (p.111) (see also [Cohen/Cvitas/etal_2007] (p. 45) and the on-line edition of the IUPAC Gold Book [IUPAC]). It is experimentally determined and its numerical value of 6.02214179 x 10^23 mol^-1 [IUPAC] is approved by IUPAC. This value is also used in the present implementation in the Quantities package. For the history of this constant, see also [Jensen_2010]). A recent determination yielded a value of 6.02214084(18) x 10^23 mol^-1 [Andreas/Azuma/etal_2010].

The Avogadro constant is closely related to the Loschmidt constant, and sometimes, e.g. in [Virgo_1933], "Loschmidt's number" has been used for the Avogadro constant.

In Quantities, the physical constant AvogadroConstant is implemented as a UniqueConstant. It is a Loki::Singleton, defined in namespace avogadroConstant.

The dimension of AvogadroConstant is $(0, 0, 0, 0, 0, -1, 0)$ .

AvogadroConstant defines the following units:

OnePerMole (composed) and prefix variants

The constant should be used as a macro AVOGADROCONSTANT:

std::cout << " L = " << AVOGADROCONSTANT << std::endl;   // prints the Avogadro constant

References

[Cohen/Cvitas/etal_2007] E.R. Cohen, T. Cvitas, J.G. Frey, B. Holmström, K. Kuchitsu, R. Marquardt, I. Mills, F. Pavese, M. Quack, J. Stohner, H.L. Strauss, M. Takami, and A.J. Thor, Quantities, Units and Symbols in Physical Chemistry, 3rd ed., Blackwell Science, Oxford, 2007.

[IUPAC] IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8; term "Avogadro constant", doi:10.1351/goldbook.A00543.

[Jensen_2010] W.B. Jensen, J. Chem. Educ. 87, 1302 (2010).

[Virgo_1933] S.E. Virgo, Sci. Prog. 27, 634 - 649 (1933).

[Andreas/Azuma/etal_2010] B. Andreas, Y. Azuma, G. Bartl, P. Becker, H. Bettin, M. Borys, I. Busch, M. Gray, P. Fuchs, K. Fujii, H. Fujimoto, E. Kessler, M. Krumrey, U. Kuetgens, N. Kumamoto, G. Mana, P. Manson, E. Massa, S. Mizushima, A. Nicolaus, A. Picard, A. Pramann, O. Rienitz, D. Schiel, S. Valkiers und A. Waseda, http://arxiv.org/abs/1010.2317 , last accessed December 28, 2010.

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