Syntheses of new di-nuclear and tetra-nuclear lanthanide 9-anthracenecarboxylates:Magnetocaloric effect,slow magnetic relaxation and luminescent properties  

作　　者：Xing Liu Ruonan Yang Lu Zhang Jian Zhou Chunmei Huang Huahong Zou Zunhong Xiao 

机构地区：[1]Chongqing Key Laboratory of Inorganic Functional Materials,College of Chemistry,Chongqing Normal University,Chongqing,401331,China [2]Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China),School of Chemistry and Chemical Engineering of Guangxi Normal University,Guilin,541004,China [3]School of Chemistry and Materials,Guizhou Normal University,Guiyang,550025,China

出　　处：《Journal of Rare Earths》2024年第6期1101-1109,I0004,共10页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(21671029);Innovation andEntrepreneurship Team of Inorganic Optoelectronic Functional Materials for Chongqing Yingcai(cstc2021ycjh-bgzxm0131);MajorProject of the Science and Technology Research Program of Chongqing Education Commission of China(KJZD-M202100501);theInnovation Program for Chongqing’s Overseas Returnees(cx2019037);Natural Science Foundation of Chongqing,China(cstc2021jcyj-msxmX0380);Chongqing Normal University(21XLB034)。

摘　　要：Lanthanide complex-based materials with magnetic and luminescent properties have received a great deal of attention,owing to their importantly potential applications in diverse fields.In this work,the 9-anthracenecarboxylic acid(9-Haca)as bridging ligand was applied in combination with optically activeπ-conjugated 2,4,6-tri(2-pyridyl)-1,3,5-triazine(tptz)to construct a series of new di-nuclear and tetranuclear lanthanide 9-anthracenecarboxylates[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]·0.25H_(2)O(1),[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]·0.5AQ·CH_(3)COOH_(2)H_(2)O[Ln=Sm(2a),Eu(2b),Gd(2c),Tb(2d),Dy(2e),Tm(2f);AQ=9,10-anthracenedione]and[Ln_(4)(9-aca)_(10)(tptz)_(2)(CH3COO)2]·H_(2)O[Ln=Eu(3a),Gd(3b),Dy(3c)].1 displays a di-nuclear centrosymmetric moiety[La_(2)(9-aca)_(6)(tptz)_(2)(μ-H_(2)O)]built up from two complex[La(9-aca)_(2)(tptz)]groups bridged by one H_(2)O molecule and two syn-syn-μ2-η1:η1-9-aca-bridging ligands,while 2a-2f are isostructural and co mprise another di-nuclear centrosymmetric moieties[Ln_(2)(9-aca)_(6)(tptz)_(2)(H_(2)O)_(2)]based on two complex[Ln(9-aca)_(2)(tptz)(H_(2)O)]groups connected by two syn-syn-μ2-η1:η1-9-aca-bridging ligands,3a-3c are isostructural and show tetra-nuclear centro symmetric moieties[Ln4(9-aca)10(tptz)2(CH3COO)2]containing three types of coordination modes of 9-aca-ligands.The present compounds offer the only examples of lanthanide 9-anthracenecarboxylates decorated by optically active tptz.Magnetic investigations of 2a,2c-2f,and 3b-3c indicate that 3c is typical of slow relaxation of the magnetization,while 2c and 3b show significant magnetocaloric effect(MCE)with the value of-ΔSm of 5.26 J/(kg·K)at 4 K and 15.65 J/(kg·K)at 2 K(ΔH=7 T),respectively.The luminescent properties were also studied and reveal that the characteristic luminescent properties of the 7r-conjugated aromatic ligands are introduced into magnetic lanthanide 9-anthracenecarboxylates,simultaneously exhibiting slow magnetic relaxation(or MCE)and luminescent properties.

关 键 词：Lanthanide complexes Luminescence Magnetic properties Magnetocaloric effect Slow magnetic relaxation Rare earths 

分 类 号：TB34[一般工业技术—材料科学与工程]