Check out this: https://www.researchgate.net/publication/244068891_Hemiprotonated_dafone_a_new_cationic_species._The_novel_di-dafonium_iron%28III%29_complex_%28dafone%29_2H_FeCl_4_?ev=prf_pub
Article Hemiprotonated dafone, a new cationic species. The novel di-...
Yes, FeCl4- anion is having experimental value of magnetic moment that is 1.73 to 1.74 BM, because Fe3+ ions having five unpaired electrones in it, on arrival of cl- ligand there occurs rearrangement of there five unpaired electrone and as a result one electrone will remain unpaires which is responsible for this paramagnetic property.