Action spectroscopy of SrCl⁺ using an integrated ion trap time-of-flight mass spectrometer.

Abstract

The photodissociation cross-section of SrCl(+) is measured in the spectral range of 36,000-46,000 cm(-1) using a modular time-of-flight mass spectrometer (TOF-MS). By irradiating a sample of trapped SrCl(+) molecular ions with a pulsed dye laser, X(1)Σ(+) state molecular ions are electronically excited to the repulsive wall of the A(1)Π state, resulting in dissociation. Using the TOF-MS, the product fragments are detected and the photodissociation cross-section is determined for a broad range of photon energies. Detailed ab initio calculations of the SrCl(+) molecular potentials and spectroscopic constants are also performed and are found to be in good agreement with experiment. The spectroscopic constants for SrCl(+) are also compared to those of another alkaline earth halogen, BaCl(+), in order to highlight structural differences between the two molecular ions. This work represents the first spectroscopy and ab initio calculations of SrCl(+).