Absorption of radiation in the extreme ultra-violet by the inert gases

Abstract

In 1910 I published a set of determinations of the refraction and dispersion of the five inert gases for eight wave lengths in the visible region, together with values of the constants C and n 0 2 in the expression μ - 1 = C/ n 0 2 - n 2 . If Drude’s form of the dispersion equation is substituted, μ 2 - 1 = ΣN e 2 /π m ( n 0 2 - n 2 , where N is the number of electrons per cubic centimetre, and n 0 the free frequency of the electrons, and it is assumed that there is only one free frequency in the molecule, it is possible to deduce from this equation the number, or apparent number, of electrons per molecule which affect dispersion and their free frequency.