| Abstract
| - We report here the X-ray magnetic circular dichroism (XMCD) study at the Gd M4,5- and L2,3-edges of two linear magnetic chains involving Gd(III) cations bridged by nitronyl nitroxide radicals. Thisspectroscopy directly probes the magnetic moments of the 4f and 5d orbitals of the gadolinium ions. Wecompare macroscopic magnetic measurements and local XMCD signals. The M4,5-edges results are inagreement with the J values extracted from the fits of the SQUID magnetic measurements. The L2,3-edgessignals show that the electronic density in the Gd 5d orbitals depends on the neighbors of the gadoliniumcations. Nevertheless, the 5d orbitals do not seem to play any role in the superexchange pathway betweenradicals through the metal ion proposed to explain the particular magnetic exchange interactions betweenthe radicals in these chains.
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