title: Two lanthanide(III)-copper(II) organic frameworks based on {OLn6 } clusters that exhibited a large magnetocaloric effect and slow relaxation of the magnetization.
abstract: Two new 3D lanthanide(III)-copper(II) organic frameworks based on unusual {OLn6} clusters have been successfully synthesized and fully characterized. Crystallographic studies showed that the {OLn6} clusters acted as 12-connected nodes that were linked together by [CuL2] (H2L = 3-hydroxypyrazine-2-carboxylic acid) moieties to construct an interesting 4,12-c net with the point symbol {4(36).6(30)}{4(4).6(2)}3. Magnetic studies revealed that these two isostructural heterometallic frameworks exhibited different magnetic properties, depending on the different anisotropies of the lanthanide spin carriers: Gd-Cu showed a large magnetocaloric effect, with an entropy change (-ΔS(m)) of 35.76 J  kg(-1)  K(-1), which is one of the largest values in high-dimensional complexes, whilst Dy-Cu exhibited slow relaxation of the magnetization at low temperatures.
authors: Department of Chemistry and Key Laboratory of Advanced Energy Materials Chemistry (MOE), Nankai University, Tianjin 300071, PR China.
authors: Yanmin
authors: Y
authors: Bing
authors: Na
authors: N
authors: Xu
authors: Wei
authors: W
authors: Shi
authors: Ke
authors: K
authors: Liu
authors: Peng
authors: P
authors: Cheng