A metal-organic framework as attractive cryogenic magnetorefrigerant.

Magnetocaloric effect: A Gd(III)-based metal-organic framework (MOF) has an unprecedented large magnetocaloric effect around 2 K. It was shown to be an interesting magnetorefrigerant for ultralow-temperature applications, because it combines the advantages of molecular materials and the robustness of a framework with strong 3D chemical connections (see figure).

Co4(OH)2(C10H16O4)3 metal-organic framework: slow magnetic relaxation in the ordered phase of magnetic chains.

Reported here are the synthesis and structural and topological analysis as well as a magnetic investigation of the new Co(4)(OH)(2)(C(10)H(16)O(4))(3) metal-organic framework. The structural analysis reveals a one-dimensional inorganic subnetwork based on complex chains of cobalt(II) ions in two different oxygen environments. Long alkane dioic acid molecules bridge these inorganic chains together to afford large distances and poor magnetic media between dense spin chains.