Interactions of low-energy electrons with the FEBID precursor chromium hexacarbonyl (Cr(CO)₆)

Interactions of low-energy electrons with the FEBID precursor Cr(CO)₆ have been investigated in a crossed electron-molecular beam setup coupled with a double focusing mass spectrometer with reverse geometry. Dissociative electron attachment leads to the formation of a series of anions by the loss of CO ligand units. The bare chromium anion is formed by electron capture at an electron energy of about 9 eV. Metastable decays of Cr(CO)₅^- into Cr(CO)₄^-, Cr(CO)₄^- into Cr(CO)₃^- and Cr(CO)₃^- into Cr(CO)₂^- are discussed. Electron-induced dissociation at 70 eV impact energy was found to be in agreement with previous studies. A series of Cr(CO) _n C⁺ (0 ≤ n ≤ 3) cations formed by C-O cleavage is described for the first time. The metastable decay of Cr(CO)₆⁺ into Cr(CO)₅⁺ and collision-induced dissociation leading to bare Cr⁺, are discussed. In addition, doubly charged cations were identified and the ration between doubly and singly charged fragments was determined and compared with previous studies, showing considerable differences.