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

摘要

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∑~+ state molecular ions are electronically excited to the repulsive wall of the A~1∏ 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~+.