The Absorption Spectra of Copper, Silver and Gold Vapors in the Ultra-violet

Abstract

Using a carbon tube heated to between 1600°C and 2000°C with an oxyacetylene torch, the absorption spectrum has been studied in the ultra-violet to 2000 A. With copper, besides strong absorption at the first pair of the principal series 3273.9 and 3247, in agreement with Grotrian, lines were found at 2225, 2182, 2178.9, 2165, 2024.3 and, with 2000°C at 2244. The second pair of the principal series has been calculated by Randall to come at 2024.4 and 2025.7, but the absence of any trace of the second line makes this identification still uncertain. With silver very strong absorption was obtained at 3382 and 3280 (as by Grotrian) and also at 2070.0 and 2061.2. These are the first two pairs of the principal series. With gold there was distinct absorption only at 2675.9 and 2427.9 indicating that these lines are the first pair of the principal series.