Paramagnetic defect centres in crystalline Alq3

被引：15

作者：

Grecu, MN

Mirea, A

Ghica, C

Cölle, M

Schwoerer, M

机构：

[1] Natl Inst Mat Phys, Bucharest 077125, Romania

[2] Univ Bayreuth, D-95440 Bayreuth, Germany

[3] Philips Res Labs, NL-5656 AA Eindhoven, Netherlands

来源：

JOURNAL OF PHYSICS-CONDENSED MATTER | 2005年 / 17卷 / 39期

关键词：

D O I：

10.1088/0953-8984/17/39/012

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

X- and Q-band electron paramagnetic resonance (EPR) investigation of different crystalline Alq(3) (tris(8-hydroxyquinoline)aluminium (III)) fractions formed by a train sublimation method are reported. Several paramagnetic defect centres corresponding to 1/2, 1, and 3/2 spin are observed at room temperature. Their intensity is dependent on the temperature, nature of the crystalline phase, and preparation conditions. Spectra simulation and analysis based on the spin Hamiltonian appropriate to a high spin system (S >=, 1) suggest the existence of randomly oriented triplets and quartets in annealed Alq(3) fractions. The crystalline Alq(3) phases responsible for the EPR powder spectra have been identified by transmission electron microscopy measurements performed on these sample fractions.

引用

页码：6271 / 6283

页数：13