Determination of the Distributions of the Spin-Hamiltonian Parameters in Spin Triangles: A Combined Magnetic Susceptometry and Electron Paramagnetic Resonance Spectroscopic Study of the Highly Symmetric [Cr₃O(PhCOO)₆(py)₃](ClO₄)·0.5py

Abstract

anisotropy to the S T = 1/2 ground state of 1, as well as an important broadening of the g ⊥ resonance (g-strain). Through careful analysis of these data, and in conjunction with neutron scattering data, this g-strain can be deconvoluted into distributions of the individual spin Hamiltonian parameters ΔJ and |G|. This method of analysis provides simultaneous estimates of the central values and distribution profiles of the spin Hamiltonian parameters, which are shown not to be described by monodisperse values.

Relevance of Dzyaloshinskii–Moriya spectral broadenings in promoting spin decoherence: a comparative pulsed-EPR study of two structurally related iron(iii) and chromium(iii) spin-triangle molecular qubits

“…60 On the other hand, these are the first such values reported for a Cr III triangle. Regarding the activation energies, these are in excellent agreement with the spin Hamiltonian parameters previously determined for Fe 3 34 and in good agreement with those determined for Cr 3 37 in the solid state ( Figure 4).…”

“…The appearance of numerous resonances reveals magnetic conformations of different effective g ⊥ values. A similar, yet much more pronounced, narrowing is observed in the Cr 3 complex which shows a spectral breadth of ~50 G (~3500-3550 G) greatly reduced with respect to the solid-state 37 (1.98-1.95 vs 1.98-1.5, respectively). This behavior is also in line with the characteristics of this complex previously published by us, indicating a much weaker DMI (G z = 0.041 cm -1 ) inducing a much weaker magnetic anisotropy.…”

“…(ii) A higher-field derivative-like feature which corresponds to z⊥B 0 (g ⊥ ) and whose value also depends on parameters ΔJ = J -J' and |G|. The CW spectra of both complexes in frozen pyridine-d 5 solutions were qualitatively similar to the solid-state ones, 28,37 albeit presenting differences in the shape and width of their non-parallel part. The CW spectrum of Fe 3 revealed resonances over a broad magnetic field range (3500-4500 G; g ~ 2.00-1.65), indicative of significant magnetic anisotropy, which is in line with the strong DMI (G z ~ 1.7-2.0 cm -1 ) determined by solid-state studies.…”

SMM-ET: An SMM Evaluation Tool for the Quantitative Treatment of Ac Susceptibility and Magnetic Hysteresis Data

“…Ueff offering a choice between Gaussian, Lorentzian or Voigtian probability density functions. Indeed, it was shown by Weihe and coworkers [37], and subsequently by this author [38] and others [39] Argand or Cole-Cole plots). We can also plot them as isofrequency/isofield χʹ,χʺ(T) plots.…”

Chromium(III)-pyrazole complexes. X-Ray crystal structures, 1H NMR investigation of ligand fluxional behavior and EPR studies

“…Due to the relevance of zero-field splitting (ZFS) in the appearance of the satellite features, and due to the minor influence of ligand-field effects on the g-tensor components and in inducing gstrains (see below), only a D-strain model was considered in order to account for parameter distributions, assuming that the g-tensor components are monodisperse. The D parameter was considered as following a normal distribution according to the methodology of recent studies considering distributed spin Hamiltonian parameters [36,37]. Fitting yielded central D values of 0.15-0.16 cm -1 for values for 1 and 3 and about half that for 4 ( Table 5).…”