Heterospin single-molecule magnets with extra-large anisotropic barrier

Daisuke Yoshihara, Satoru Karasawa, Noboru Koga

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

The mixtures of Co(X-hfpip)2; X = I and H, and bisdiazo-dipyridine ligands, D2py2(TBA), in 1:1 ratios gave the discrete cobalt complexes, 1 and 2, respectively. The molecular structures for 1 and 2 revealed by X-ray crystallography were cyclic 2:2 cobalt complexes formulated as [(Co(X-hfpip)2)2(D2py2(TBA)) 2], in which the cobalt units were compressed octahedra. After irradiation of the microcrystalline samples, the resulting Co-carbene complexes, 1c and 2c, showed SMM behaviors exhibiting slow magnetic relaxations. In dc and ac magnetic susceptibility experiments, the activation barrier, U eff, for reorientation of the magnetic moment were estimated to be 139 and 135 K for 1c and 2c, respectively, and the hysteresis loops of the magnetization (the coercive force, Hc, and 26 and 15 kOe at 1.9 K for 1c and 2c, respectively) were observed. In addition, the values of the quantum tunneling time, τQ, were determined to be 1.1 × 10 5 and 5.4 × 105 s (t1/2 = 21 and 104 h) for 1c and 2c, respectively, below 2.5 K.

Original languageEnglish
Pages (from-to)3211-3217
Number of pages7
JournalPolyhedron
Volume30
Issue number18
DOIs
Publication statusPublished - Nov 28 2011

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Cobalt
Magnets
magnets
cobalt
Molecules
Magnetic relaxation
molecules
X ray crystallography
magnetic relaxation
carbenes
Hysteresis loops
Coercive force
Magnetic moments
Magnetic susceptibility
Molecular structure
crystallography
retraining
Magnetization
molecular structure
magnetic moments

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry
  • Materials Chemistry

Cite this

Heterospin single-molecule magnets with extra-large anisotropic barrier. / Yoshihara, Daisuke; Karasawa, Satoru; Koga, Noboru.

In: Polyhedron, Vol. 30, No. 18, 28.11.2011, p. 3211-3217.

Research output: Contribution to journalArticle

Yoshihara, Daisuke ; Karasawa, Satoru ; Koga, Noboru. / Heterospin single-molecule magnets with extra-large anisotropic barrier. In: Polyhedron. 2011 ; Vol. 30, No. 18. pp. 3211-3217.
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