RESUMEN
Here we reported the deuteration of the metal-binding equatorial water molecules in a reported HoIII single-molecule magnet (SMM) with pentagonal-bipyramidal geometry, from [Ho(CyPh2 PO)2 (H2 O)5 ]3+ to [Ho(CyPh2 PO)2 (D2 O)5 ]3+ . The hyperfine structures originating from the nuclear spin of 165 HoIII can be clearly observed. Moreover, the resulting magnetization dynamics revealed the switch of the relative relaxation rates for the two isotope-isomorphic complexes-respectively faster/slower at low/high temperature. The noticeable isotope effect arises from not only the paramagnetic metal center but also the diamagnetic ligands, which can be explained by the ab initio calculated tunnel splitting and the involvement of the super-hyperfine interaction related to the difference in the nuclear spin number of protium (1 H, I=1 /2 ) and deuterium (2 H, I=1).
RESUMEN
A Gadolinium EDTA chelate displays characteristic isotropic behaviour common of Gd(III) complexes under zero applied magnetic field, and anisotropic behaviour arising from dipolar coupling and weak spin-phonon coupling under an applied magnetic field. This surprising magnetic behaviour for Gd(III) is investigated using SQUID magnetometry and rationalized through theoretical calculations.
RESUMEN
Using the contour integration approach proposed earlier, we find a simple derivation of the Landau-Zener formula which does not use explicitly the solution of the Schrödinger equation.