Complex sentence: Being a typical member of the lanthanide series, samarium usually assumes the oxidation state +3; however, compounds of samarium (II) are also known, most notably monoxide SmO, monochalcogenides SmS, SmSe and SmTe, as well as samarium (II) iodide.
Split into simpler sentences: Being a typical member of the lanthanide series, samarium usually assumes the oxidation state +3. Compounds of samarium (II) are also known, most notably monoxide SmO, monochalcogenides SmS, SmSe and SmTe, as well as samarium (II) iodide.