p [0:2] "OPTICS_0.005_-0.03/FeSi.oc" u 1:2 t "OPTICS_0.005_-0.03/FeSi.oc u 1:2" w l lw 2, "OPTICS_0.005/FeSi.oc" u 1:2 t "OPTICS_0.005/FeSi.oc u 1:2" w l lw 2