set size square
set xrange [-1.1:1.1]
set yrange [-1.1:1.1]
set xlabel "Re(V)"
set ylabel "Im(V)"
set xzeroaxis
set yzeroaxis
set object circle at 0,0 size 1

do for [ii=start:end] {
    plot 'data' every ::ii::ii * states using 4:5:6 w points palette pointsize 2 pointtype 7, \
         'data' every ::1::ii * states using 4:5:6 w l palette lw 3
    pause 0.1
}

pause mouse close