Substituted aryl pnictogen derivative compositions having the structure of [R.sub.f.sup.1--(C.sub.tR.sub.(u+v))].sub.mE(O).sub.n(C.sub.tR.sup.1.sub.- (u+v+1)).sub.(3-m)wherein E is phosphorous, arsenic or antimony; R.sub.f.sup.1 is a fluoropolyether chain; C.sub.tR.sub.(u+v) and C.sub.tR.sup.1.sub.(u+v+1) represent aryl groups, n is 0 or 1 and m is greater than about 0.5 to about 3. Such compositions have utility as additives for high temperature lubricants.