On the stability of isolated dianions in vacuo and action spectroscopy experiments

Tetrathiocyanoplatinate(II), Pt ( SCN ) 4 2 - , isolated in vacuo was subjected to a range of experiments. From storage ring measurements the dianions were found to be stable on the seconds time scale. At another instrumental setup, ions were photoexcited with UV light, and the dominant decay channel was electron detachment. The yield of Pt ( SCN ) 4 - monoanions as a function of wavelength provided the action spectrum. Maximum absorption occurs at ∼240 nm, and the spectrum is similar to the absorption spectrum of Pt ( SCN ) 4 2 - in methanol solution, which implies that a solvent perturbs the ground state and the electronically excited state in the same manner.