I'm currently doing a project where I analyze the Spin-Crossover phenomena in 4 different iron complexes. I managed to synthesis 3 complexes with: iron (II)-iodide, bromide and chloride. (I used l-ascorbic acid to prevent the oxidation of iron (+ N2) and I used 4-amino-1,2,4-tirzole as ligand and methanol as the solvent). Now I stuck with Iron(II)-fluoride. It never really worked; the beige powder never dissolved in the solution. I used 4 different solvents, first I used methanol like the others, then I used distilled water, then I used Dimethyl sulfoxide (DMSO) (it was organic so obviously it didn’t work) and at the end I used Tetrahydrofuran (THF). None of these worked and my last guess would be to use HF (hydrofluoric acid). Though my school does not have this chemical right now. Does anybody of you guys maybe know how to dissolve iron(II)-fluoride, maybe heat it or something?