We report on a comparative study of electronic and magnetic properties of Mn6single-molecule magnets (SMMs) grafted on gold surface. Two derivatives with spin-ground states S = 4 and S = 12 have been functionalized with 3-tp-CO2-(3-thiophene carboxylate, tpc) ligands and characterized as thick films (TFs) as well as sub-monolayers (sMLs) by synchrotron based techniques. X-ray absorption spectroscopy at the Mn L2,3edges shows the modification of the spectral lineshape in the sMLs with respect to the TFs suggesting that the local symmetry at the Mn sites changes once the molecules are deposited on gold surface. In spite of this, the expected MnIIIoxidation state is preserved. X-ray magnetic circular dichroism (XMCD) spectra show that the total magnetic moment is only given by spin part because of the quenched orbital moment. Moreover, variable temperature and variable field XMCD spectra reveal an effective decrease of the Mn spin moment for both derivatives. © 2010 The Royal Society of Chemistry
Moro, F., Corradini, V., Evangelisti, M., Biagi, R., De Renzi, V., Del Pennino, U., et al. (2010). Addressing the magnetic properties of sub-monolayers of single-molecule magnets by X-ray magnetic circular dichroism. NANOSCALE, 2(12), 2698-2703 [10.1039/c0nr00483a].
Addressing the magnetic properties of sub-monolayers of single-molecule magnets by X-ray magnetic circular dichroism
Moro, Fabrizio;
2010
Abstract
We report on a comparative study of electronic and magnetic properties of Mn6single-molecule magnets (SMMs) grafted on gold surface. Two derivatives with spin-ground states S = 4 and S = 12 have been functionalized with 3-tp-CO2-(3-thiophene carboxylate, tpc) ligands and characterized as thick films (TFs) as well as sub-monolayers (sMLs) by synchrotron based techniques. X-ray absorption spectroscopy at the Mn L2,3edges shows the modification of the spectral lineshape in the sMLs with respect to the TFs suggesting that the local symmetry at the Mn sites changes once the molecules are deposited on gold surface. In spite of this, the expected MnIIIoxidation state is preserved. X-ray magnetic circular dichroism (XMCD) spectra show that the total magnetic moment is only given by spin part because of the quenched orbital moment. Moreover, variable temperature and variable field XMCD spectra reveal an effective decrease of the Mn spin moment for both derivatives. © 2010 The Royal Society of ChemistryI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.