两种双核稀土配合物的光致变色和光磁效应

Photochromism and Photomagnetism in Two Dinuclear Lanthanide Complexes

利用光诱导电子转移机理和配位驱动组装策略探索室温光磁效应材料的合成.通过组装稀土硝酸盐与1,10-菲罗啉(phen)获得2种同构双核稀土配合物[Ln_(2)(NO_(3))_(6)(phen)_(2)](1:Ln=Gd;2:Ln=Dy).由于具有电子给体-受体结构特征,目标产物在光照后发生电子转移,电子由硝酸根的氧原子转移到phen的氮原子,进而产生光生自由基并发生肉眼可见的颜色变化.除光致变色外,配合物1和2在室温下具有光磁效应.本研究为构筑室温光致变色和光磁效应杂化材料提供了一种通用方法:配位组装顺磁金属盐与菲罗啉衍生物.

Photomagnetic materials have many potential applications in assorted domains because of the merge of molecular electronics and molecular magnetism in one material.Hitherto,most of these materials feature photomag⁃netic performance at low temperature,which heavily restrict their applications.Thus,it is necessary to enlarge the working temperature for practical application.Herein,we utilized the photoinduced electron transfer(ET)strategy in the photochromic material system to quest photomagnetic materials at ambient temperature,that is,coordination-driven assembly of lanthanide nitrates and 1,10-phenanthroline(phen).The resultant complexes,[Ln_(2)(NO_(3))_(6)(phen)_(2)](Ln=Gd for 1 and Dy for 2),featured isostructural discrete dinuclear structure with electron donor-electron acceptor characteristic.Photogenerated radicals driven by ET from the electron-donating nitrate to electron-accepting phen were produced after photoirradiation.Besides the eye-detectable photochromism,the photomagnetism was also present at room temperature.This study provides a general method to synthesize hybrid materials bearing photochro⁃mic and photomagnetic performance via hybridizing paramagnetic metal salt with phenanthroline derivatives.