engleski

Pressure effect in TDAE-C60ferromagnet: Mechanism and polymerization

Effects of hydrostatic pressure on TDAE-C-60 an investigated by electron spin resonance to reveal a mechanism of the ferromagnetism, where TDAE is tetrakis-dimethylamino-ethylene. T-C decreases with increasing pressure, reaching zero around 9 kbar, following a relation of approximate to T-C(0)(1 - aP(2)). The orbital- ordering model of Jahn-Teller distorted C-60 molecules reproduces such a dependence successfully. Furthermore, above approximate to 10 kbar at 300 K, alpha -TDAE-C-60 transforms to the beta phase with a [2+2] cycloadditive one-dimensional polymer, stable even after pressure release. Remarkably, a missing spin in TDAE(+) revives in the polymer with g = 2.0028.

Jahn-Teller distortion ; magnetic properties ; single crystal ; ESR ; TDAE ; tetrakis(dimethylamino)ethylene ; electron ; cations ; states

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