The polymer phase of the TDAE-C${}_{60}$ organic ferromagnet

Abstract

The high-pressure Electron Spin Resonance (ESR) measurements were preformed on TDAE-C${}_{60}$ single crystals and stability of the polymeric phase was established in the $P-T$ parameter space. At 7 kbar the system undergoes a ferromagnetic to paramagnetic phase transition due to the pressure-induced polymerization. The polymeric phase remains stable after the pressure release. The depolymerization of the pressure-induced phase was observed at the temperature of 520 K. Below room temperature, the polymeric phase behaves as a simple Curie-type insulator with one unpaired electron spin per chemical formula. The TDAE${}^{+}$ donor-related unpaired electron spins, formerly ESR-silent, become active above the temperature of 320 K and the Curie-Weiss behavior is re-established.

Submitted to Phys. Rev. B

References in corpus (2)

• Critical exponents at the ferromagnetic transition in tetrakis(diethylamino)ethylene-C${}_{60}$ (TDAE-C${}_{60}$)
• Theoretical Study of Pressure Effect on TDAE-C60