set output 'lennard_c.ps' 
set term postscript color enhanced 'Helvetica,18'  
set style line 1 lt rgb 'red' lw 3  
set style line 2 lt rgb 'green' lw 3  
set style line 3 lt rgb 'blue' lw 3  
set style line 4 lt rgb 'cyan' lw 3  
set style line 5 lt rgb 'violet' lw 3  
set grid 
set key top right 
set ylabel 'Potential energy U' 
set xlabel 'Position x' 
plot [1.102:1.142][-0.251:-0.246] ( (1/x)**12 - (1/x)**6 ) ls 1 lw 3 t ''  
set output 
quit 
