Wet electrons and how to dry them

We present the formation of hydrated electrons by laser vaporization, and investigate in a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer their destruction by the 300 K black body infrared background radiation. While clusters above n⩾32 decay almost exclusively by fragmentation and loss of ligands, the smaller species also detach electrons, with the relative rates of the two processes exhibiting an interesting alternation. Below n=15 they almost exclusively detach electrons, and for n⩽12 the detachment rate is apparently so fast that no clusters are observed in the ICR-experiment. From n=19 to n=24 a pronounced odd–even alternation between electron detachment and fragmention is observed, which is tentatively attributed to entropic rather than energetic effects.