简介概要

Relaxation process and phase transition of lanthanide liquid crystalline complexes by photoacoustic spectroscopy

来源期刊:Journal of Rare Earths2008年第3期

论文作者:李俊嘉 杨跃涛 刘晓峻 张淑仪 张仲宁

文章页码:320 - 325

摘    要:Lanthanide-containing liquid crystals exhibiting smectic A phase close to room temperature were obtained. Photoacoustic (PA) spectroscopy was used to study the spectral properties and phase transitions of liquid crystalline metal complexes. It was found that PA intensity of the ligand had a relationship with the probability of nonradiative transitions, which increased in the order of Eu(tta)3L2<La(tta)3L2< Tb(tta)3L2<Er(tta)3L2. The relaxation processes of the complexes were studied in depth from two aspects: radiative and non-radiative processes, combining with their fluorescence spectra. Phase transitions of europium(III) and erbium(III) complexes, in the temperature range of 383-358 K, could be clearly monitored by both PA amplitude and PA phase signals. As the temperature crossed the transition point, PA amplitude showed a minimum and PA phase a maximum. The results indicated that PA technique could serve as a new tool for investigating the physicochemical properties of liquid crystals containing metal ions.

详情信息展示

Relaxation process and phase transition of lanthanide liquid crystalline complexes by photoacoustic spectroscopy

李俊嘉,杨跃涛,刘晓峻,张淑仪,张仲宁

摘 要:Lanthanide-containing liquid crystals exhibiting smectic A phase close to room temperature were obtained. Photoacoustic (PA) spectroscopy was used to study the spectral properties and phase transitions of liquid crystalline metal complexes. It was found that PA intensity of the ligand had a relationship with the probability of nonradiative transitions, which increased in the order of Eu(tta)3L2<La(tta)3L2< Tb(tta)3L2<Er(tta)3L2. The relaxation processes of the complexes were studied in depth from two aspects: radiative and non-radiative processes, combining with their fluorescence spectra. Phase transitions of europium(III) and erbium(III) complexes, in the temperature range of 383-358 K, could be clearly monitored by both PA amplitude and PA phase signals. As the temperature crossed the transition point, PA amplitude showed a minimum and PA phase a maximum. The results indicated that PA technique could serve as a new tool for investigating the physicochemical properties of liquid crystals containing metal ions.

关键词:

<上一页 1 下一页 >

有色金属在线官网  |   会议  |   在线投稿  |   购买纸书  |   科技图书馆

中南大学出版社 技术支持 版权声明   电话:0731-88830515 88830516   传真:0731-88710482   Email:administrator@cnnmol.com

互联网出版许可证:(署)网出证(京)字第342号   京ICP备17050991号-6      京公网安备11010802042557号