摘要:SummaryUnpaired electrons which are essential for organic radicals and magnetic materials are hardly to align parallel, especially upon the increasing of spin numbers. Here, we show that the antiferromagnetic interaction in the largest Cr(III)-RE (rare earth) cluster {Cr10RE18} leads to 96 parallel electrons, forming a ground spin stateSTof 48 for RE = Gd. This is so far the third largest ground spin state achieved in one molecule. Moreover, by using the classical Monte Carlo simulation, the exchange coupling constantsJijcan be determined. Spin dynamics simulation reveals that the strong Zeeman effects of 18 Gd(III) ions stabilize the ground ferrimagnetic state and hinder the magnetization reversals of these spins. In addition, the dysprosium(III) analog is an exchange-biasing single-molecule magnet. We believe that the ferrimagnetic approach and analytical protocol established in this work can be applied generally in constructing and analyzing giant spin molecules.Graphical abstractDisplay OmittedHighlights•The largest {Cr10RE18} molecular clusters were assembled for RE = Gd, Dy, and Y•The {Cr10Gd18} cluster shows a large ground spin state ofST = 48•The exchange coupling constants were determined by Classical Monte Carlo simulation•Spin dynamics simulation reveals a ferrimagnetic ground state of {Cr10Gd18}.Chemistry; Inorganic Chemistry; Molecular Inorganic Chemistry; Magnetism