The present invention provides compounds represented by the formula Y.sup.+-N(SO.sub.2R.sup.f)(CF.sub.3). Such a compound can be manufactured through a reaction between M.sup.+-N(SO.sub.2R.sup.f)(CF.sub.3) and Y.sup.+-B. The present invention also provides compounds represented by the formula Y.sup.+-N(SO.sub.2R.sup.f)(CN). Such a compound can be manufactured through a reaction between M.sup.+-N(SO.sub.2R.sup.f)(CN) and Y.sup.+-B. R.sup.f in the above formulae is a perfluoroalkyl group. Y.sup.+ is an organic or inorganic cation. .sup.-B is an organic or inorganic anion. M.sup.+ is an alkali metal cation or a silver cation.