Dielectric spectroscopy is applied to the study of phase transitions in the range from room temperature down to 12 K in single crystals of tetracene (TEN), a well known material which, as most organic semiconductors, shows polymorphism. The present analysis, through proper experimental procedures, permits to identify the wide range (T > 150 K) of instabilities and of strong hysteresis effects as clear evidence of a non-ergodic state, then also clarifying some open questions, first of all the role of the sample thermal history, including the temperature variation rate and some apparent sample-dependence of the results. Furthermore evidence is obtained of two transitions at 144 K and 45 K
Parravicini, G., Campione, M., Marabelli, F., Moret, M., Sassella, A. (2012). Experimental assessment of nonergodicity in tetracene single crystals. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 86(2) [10.1103/PhysRevB.86.024107].
Experimental assessment of nonergodicity in tetracene single crystals
CAMPIONE, MARCELLO;MORET, MASSIMO;SASSELLA, ADELE
2012
Abstract
Dielectric spectroscopy is applied to the study of phase transitions in the range from room temperature down to 12 K in single crystals of tetracene (TEN), a well known material which, as most organic semiconductors, shows polymorphism. The present analysis, through proper experimental procedures, permits to identify the wide range (T > 150 K) of instabilities and of strong hysteresis effects as clear evidence of a non-ergodic state, then also clarifying some open questions, first of all the role of the sample thermal history, including the temperature variation rate and some apparent sample-dependence of the results. Furthermore evidence is obtained of two transitions at 144 K and 45 KI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.