Naslov
Fast motion in molecular solids at low temperatures: evidence from a pulsed EPR study of nitroxyl radical relaxation

Autori
Kveder, Marina ; Jokić, Milan ; Rakvin, Boris

Izvornik
The Journal of chemical physics (0021-9606) 134 (2011), 4; 044531, 8

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
boson peak ; glass ; relaxation

Sažetak
We have investigated the electron phase-memory relaxation time of the nitroxyl radical TEMPO at temperatures between 5 and 80 K in crystalline and glassy states of ethanol using pulsed X-band electron paramagnetic resonance spectroscopy. The results indicate that the transition from the slow to fast motion regimes of the paramagnetic center occurs upon further cooling of the sample below ca. 20 K. We provide experimental evidence that this phenomenon cannot be ascribed to the impact of hyperfine interactions with methyl protons in the system but it can be instead a signature of the coupling of the electron spin with the boson peak excitations of the lattice.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA