Anisotropy of charge and spin motion in perylene hexafluoroarsenate salts

Abstract

Conduction electron spin echo attenuation in well defined magnetic field gradients provides more accurate values of the anisotropy of electron spin motion than microwave conductivity measurements. The electron spin diffusion coefficient for motion along the perylene (PE) radical cation stack, D (T ), in the PE hexafluoroarsenate salt is influenced temperature dependently by perpendicular-to-stack motion and reflects the varying average unrestricted chain length, l (T ). The anisotropy of D (T ):D ⊥ (T ) is larger than 7300:1 at 250 K.

Longitudinal and transverse diffusion of conduction-electron spins on stacks of fluoranthene radical cations

“…͑2͒ can nevertheless be separated and reliable values of D Ќ ͑T͒ are obtained. 49 Analysis of the spin diffusion coefficient parallel to the preferred direction, D ʈ ͑T͒, is much more complicated, because its absolute value is so large that the free-diffusion length…”