Ionization and photofragmentation of Ru3(CO)12 and Os3(CO)12

Abstract

In this paper, we use a combination of photoelectron spectroscopy, mass spectrometry, and density functional theory calculations to get a detailed understanding of valence single and double ionization and the subsequent dissociation processes. This is exemplified on benchmark systems, trimetallo-dodecacarbonyls M 3 (CO) 12 with M = Ru, Os, where the energy remaining in the molecule after photoionization can be retrieved by measuring the degree of fragmentation of the molecular ion. The intensity of different mass peaks can thus be directly related to ionization cross sections obtained by photoelectron spectroscopy. We find that the M-CO dissociation energy rises as the number of CO ligands decreases due to dissociation. Moreover, ionization of the CO ligands has a higher cross section than that of the metal center for both single and double ionization. After advanced fragmentation, a CO bond can break and the carbon atom remains bonded to the metal core. In addition, we found that the valence ionization cross sections of M 3 (CO) 12 are maximal at about 40 eV photon energy thus showing a more pronounced shape resonance than Ru and Os-complexes with a single metal atom center. Finally, an np → nd giant resonance absorption causes a significant increase of the ionization cross section above 50 eV for Ru 3 (CO) 12 . C 2015 AIP Publishing LLC. [http://dx

Metal Carbonyls for the Biointerference-Free Ratiometric Surface-Enhanced Raman Spectroscopy-Based Assay for Cell-Free Circulating DNA of Epstein-Barr Virus in Blood

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Additive Nano-Lithography with Focused Soft X-rays: Basics, Challenges, and Opportunities

“…A potential strength, however, may be photon energy dependent fragmentation of precursor molecules, which has potential to further enhance the in-situ purity of the resulting FXBID deposits. It has been shown that X-ray induced fragmentation of certain relevant precursor molecules exhibits photon energy dependency not only in terms of fragmentation rates, but also fragmentation chemistry, i.e., changing relative intensities of various fragments [103,118,119]. Such effects could be exploited to select photon energies for FXBID that result in a high ratio of low mass fragments (in ideal cases only the metal center itself) versus high mass fragments leading to implantation of a large amount of alien atoms from the ligands into the resulting deposits.…”

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