The Loschmidt Constant

The Loschmidt number is related to the Avogadro constant, but, although it is sometimes erroneously identified with it, is a different fundamental physical constant, defining the number of molecular entities in one cubic metre of gas under standard conditions (273.15 K, 101.325 kPa). Its value is given as 2.6867774 x 10^25 m^{-3} [NIST] (2006 CODATA recommended values).

LoschmidtConstant is implemented as a UniqueConstant. It is a Loki::Singleton, defined in namespace loschmidtConstant.

The dimension of LoschmidtConstant is $(-3, 0, 0, 0, 0, 0, 0)$ .

LoschmidtConstant defines the following units:

OnePerCubicMetre (composed) and prefix variants

The constant should be used as a macro LOSCHMIDTCONSTANT:

std::cout << " n_0 = " << LOSCHMIDTCONSTANT << std::endl;   // prints the Loschmidt constant

References

[NIST] The NIST Reference on Constants, Units, and Uncertainty, http://physics.nist.gov/cgi-bin/cuu/Value?n0|search_for=loschmidt

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