Trigonal bipyramidal Ni(II) complex [Ni(Me6tren)Cl](ClO4) (1, Me6tren = tris[2-(dimethylamino)ethyl]amine) has recently been shown by Ruamps and coworkers to possess large, uniaxial magnetic anisotropy (J. Am. Chem. Soc. 2013, 135, 3017). Their HF-EPR studies gave rhombic zero-field-splitting (ZFS) parameter E = 1.56(5) cm-1 for 1. However, the axial ZFS parameter D has not been determined. We have used far-IR magnetic spectroscopy (FIRMS) at 0-17.5 T and 5 K to probe the magnetic transitions between the MS = 1 and MS = 0 states of the ground spin state S = 1 in 1. Direct observation of the transitions between Zeeman-split states in FIRMS give axial ZFS parameter D = -110.7(3) cm-1. Hirshfeld surface analysis of the crystal structure of 1 has been performed, revealing the interactions between the cation and anion in a molecule of 1 as well as among the molecules of 1 in crystals.
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Applying Unconventional Spectroscopies to the Single‐Molecule Magnets, Co(PPh 3 ) 2 X 2 (X=Cl, Br, I): Unveiling Magnetic Transitions and Spin‐Phonon Coupling
Large separation of magnetic levels and slow relaxation in metal complexes are desirable properties of single‐molecule magnets (SMMs). Spin‐phonon coupling (interactions of magnetic levels with phonons) is ubiquitous, leading to magnetic relaxation and loss of memory in SMMs and quantum coherence in qubits. Direct observation of magnetic transitions and spin‐phonon coupling in molecules is challenging. We have found that far‐IR magnetic spectra (FIRMS) of Co(PPh3)2X2(
- NSF-PAR ID:
- 10233288
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 27
- Issue:
- 43
- ISSN:
- 0947-6539
- Format(s):
- Medium: X Size: p. 11110-11125
- Size(s):
- ["p. 11110-11125"]
- Sponsoring Org:
- National Science Foundation
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