The use of autoionizing states for efficient detection of Sr in resonance ionization mass spectrometry

Journal article, 1991

An efficient excitation scheme for RIMS of Sr has been investigated. Two-colour excitation has been used for excitation of the atoms to an autoionization level with both transitions in the visible region. The first step excitation was at 460.733 nm (5s2 1S0 -> 5s5p 1P1) and the second step leading to ionization was at 405.32 nm which connects the first excited state with a 1D2 autoionizing state at 46380 cm-1. This type of RIMS excitation scheme ensures selectively in both steps as well as an efficient degree of ionization. The choice of the visible wavelength helps also to minimize the influence of spectral interference as well as wing excitations of matrix species.