Electron correlation effects in band structure of magnetic clusters Mn12 and Fe8

Valence electronic structure of sublimated Fe4single-molecule magnets: an experimental and theoretical characterization

“…Obviously, the higher the degree of complexity is, the lower the volatility of the cluster would be, and thus, the lower is the possibility to get highly resolved UPS spectra. Indeed, the few attempts to probe the density of states (DOS) of more complex systems such as SMMs (in the form of powders or self-assembled monolayers) have required the use of different and complementary spectroscopies (variable energy photoemission, 22,23 resonant photoemission, 24,25 valence band X-ray photoemission and X-ray emission spectroscopy 26,27 ), with less details compared to UPS. In most of the aforementioned studies, theoretical calculations have been proven to be crucial to disentangle the contribution given by the orbitals of the metals and the ligands in the total density of states (TDOS).…”

“…This approach, already tested on other SMMs like Mn 6 (ref. 24) and Mn 12 , 25,26,37 is applied here to Fe 4 (dpm) 6 and Fe 4 (pta) 6 . Through the DFT + U, the different element/orbital contributions can be selectively discerned, once the approach has been tuned to a reliable "parameter-free" (hybrid functional) approach and/or to experimental observables.…”

“…Within the Fe 4 family, these two clusters are the only ones that have been successfully sublimated in ultra-high vacuum (UHV) conditions, 13,15 preserving unaltered their magnetic properties. Indeed, the few attempts to probe the density of states (DOS) of more complex systems such as SMMs (in the form of powders or self-assembled monolayers) have required the use of different and complementary spectroscopies (variable energy photoemission, 22,23 resonant photoemission, 24,25 valence band X-ray photoemission and X-ray emission spectroscopy 26,27 ), with less details compared to UPS. In particular, in this paper, ultra-violet photoemission spectroscopy, UPS, has been employed to investigate the density of the occupied molecular orbitals, with a focus on the electronic differences induced by the two different ligands, i.e.…”

X-ray Fluorescence Spectroscopy of Novel Materials

“…In particular, a large body of experimental data on the electronic structure of strongly correlated compounds of d and f metals [110][111][112][113][114][115][116][117][118][119], fullerenes [6,[120][121][122][123], molecular magnets [124][125][126][127], and new layered MgB 2 -type superconductors [31,[128][129][130][131][132] is left beyond the scope of this review, as is the influence of polarization effects on RIXS spectra [133−138]. The method in question is expected to progress along several lines.…”

Effect of Ligand Substitution on the Exchange Interactions in {Mn12}-Type Single-Molecule Magnets

“…For our electronic structure calculation we use the LMTO-ASA [25] method implemented in the Stuttgart TB-47 code. This approach was successfully adopted by us earlier for studying {Mn 12 } [6,24], {Mn 6 } [27], {Mn 4 } [7], {V 15 As 6 } [28], {V 12 As 8 } [29], and {Fe 8 } [30] spin clusters. The spin-polarized LDA+U calculations taking into account the spin-orbit interactions are computationally expensive and could be used only for simple systems [31].…”