Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand  

作　　者：Pei-Yu Liao Yu-Quan Qi Zhen Li Jian-Hua Jia Ming-Liang Tong 

机构地区：[1]Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education,School of Chemistry,Sun Yat-Sen University,Guangzhou,510006,China

出　　处：《Journal of Rare Earths》2024年第7期1298-1303,I0004,共7页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(22131011,22071274,21821003);the Pearl River Talent Plan of Guangdong(2017BT01C161)。

摘　　要：On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule magnets.Therefore,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide complexes.Herein,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied field.Further fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman processes.High-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light excitation.The absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room temperature.This study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关 键 词：Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths 

分 类 号：O641.4[理学—物理化学]