<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Crystalline phases obtained by reactions of MSO<sub>3</sub>F (M: Na, K, Rb, Cs), AgSO<sub>3</sub>F, and (SO<sub>3</sub>F)<sub>2</sub> (77 K → room temp., 2—5 d) are characterized by powder XRD, Raman spectroscopy, and magnetic measurements.</p> </abstract>