• Zamudio-Bayer, V.; Hirsch, K.; Langenberg, A.; Kossick, M.; Ławicki, A.; Terasaki, A.; v. Issendorff, B.; Lau, J.T.: Direct observation of high-spin states in manganese dimer and trimer cations by x-ray magnetic circular dichroism spectroscopy in an ion trap. The Journal of Chemical Physics 142 (2015), p. 234301/1-6

10.1063/1.4922487
Open Access Version (externer Anbieter)

Abstract:
The electronic structure and magnetic moments of free Mn+2 and Mn+3 are characterized by 2p x-ray absorption and x-ray magnetic circular dichroism spectroscopy in a cryogenic ion trap that is coupled to a synchrotron radiation beamline. Our results directly show that localized magnetic moments of 5 mB are created by 3d 5(6S) states at each ionic core, which are coupled ferromagnetically to form molecular high-spin states via indirect exchange that is mediated in both cases by a delocalized valence electron in a singly occupied 4s derived antibonding molecular orbital with an unpaired spin. This leads to total magnetic moments of 11 mB for Mn+2 and 16 mB for Mn+3, with no contribution of orbital angular momentum.