Published November 12, 2019 | Version v1
Journal article Open

Broad-Band Dielectric Spectroscopy Reveals Peak Values of Conductivity and Permittivity Switching upon Spin Crossover

Creators

  • 1. Faculty of Electrical Engineering and Computer Science and MANSiD Research Center, Stefan cel Mare University, 13, Strada Universitatii, Suceava 720229, Romania
  • 2. LCC, CNRS and Universitéde Toulouse, F-31077 Toulouse, France
  • 3. CIRIMAT, CNRS and Universitéde Toulouse, F-31068 Toulouse, France

Description

We use broad-band dielectric spectroscopy to investigate the spin-state dependence of electrical properties of the [Fe(Htrz)2(trz)](BF4) spin crossover complex. We show that the Havriliak–Negami theory can fully describe the variation of the complex dielectric permittivity of the material across the pressure–temperature phase diagram. The analysis reveals three dielectric relaxation processes, which we attribute to electrode/interface polarization, dipole relaxation, and charge transport relaxation. The contribution of the latter appears significant to the dielectric strength. Remarkably, the permittivity and conductivity changes between the high spin and low spin states are amplified at the corresponding relaxation frequencies.

Files

17.pdf

Files (1.9 MB)

Name Size Download all
md5:408f92b997d99b6cb093b66ecc9c3670
1.9 MB Preview Download

Additional details

Funding

SPINSWITCH – Multifunctional Spin Crossover Materials 734322
European Commission