Magnetic anisotropy and structural flexibility in the field-induced single ion magnets [Co{(OPPh₂)(EPPh₂)N}₂], E = S, Se, explored by experimental and computational methods

Abstract

The electronic and magnetic properties of the tetrahedral Co(ii) complexes [Co{(OPPh2)(EPPh2)N}2], E = S, Se, are explored by experimental and computational methods, and discussed with respect to their structural features.

A hundredfold enhancement of relaxation times among Er(iii) single-molecule magnets with comparable energy barriers

“…These values are beyond the common range of 2-9 for the Raman relaxation process, probably because of the participation of the phonon bottleneck process. 54,55 Despite the different ligand substitution patterns in these complexes, the electronic structure of the metal ions in these complexes are similar as they are situated in a similar local coordination environment. As such, the differences in U eff for the Orbach process or the n values for the Raman process should be small, as indeed observed.…”

Spectroscopic techniques to probe magnetic anisotropy and spin–phonon coupling in metal complexes

“…Sometimes, the combined use of FIRMS with high-field EPR (HFEPR) leads to the determination of spin-Hamiltonian parameters D, E and g for transition metal complexes. 37,54,55,57,[59][60][61][62] Each of the spectroscopies will be briefly overviewed first, followed by discussion of their use for complexes 1 and 2. The use of HFEPR has been reviewed 30,38,39 and, other than a summary in Table 1, it will not be discussed below.…”

“…In recent years, FIRMS has been extensively used to probe magnetic excited states in both d- 31,35,37,40,51,[53][54][55][56][57][58][59][60][61][62] and f-element complexes, 33,52,59,[63][64][65][66] providing understandings of magnetic anisotropy.…”

“…30,[38][39][40][41] Sometimes, simulating HFEPR spectra or combining HFEPR and DC data fitting may measure larger ZFS, [42][43][44][45][46] although using the DC data fitting here may not give reliable ZFS parameters. Using FIRMS, 31,33,35,37,40,[47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66] frequency-domain-Fourier-transform-terahertz-EPR spectroscopy (FD-FT-THz-EPR), 54,67,68 and INS [69][70][71][72][73][74][75][76][77][78][79] to determine magnetic excited levels and anisotropy has been reported. It should be pointed out ...…”

“…30,38–41 Sometimes, simulating HFEPR spectra or combining HFEPR and DC data fitting may measure larger ZFS, 42–46 although using the DC data fitting here may not give reliable ZFS parameters. Using FIRMS, 31,33,35,37,40,47–66 frequency-domain-Fourier-transform-terahertz-EPR spectroscopy (FD-FT-THz-EPR), 54,67,68 and INS 69–79 to determine magnetic excited levels and anisotropy has been reported. It should be pointed out that magnetic anisotropy of metal complexes has also been determined by cantilever torque magnetometry (CTM) 74,80–86 which was recently reviewed by Perfetti, 87 angle-resolved magnetometry, 88–91 and μ-SQUID magnetometry used by, e.g.…”