############################################################################################# # A gnuplot script to plot the finite well potential and the first few # states of the finite quantum well for V0 = 0.5 Hartrees and L0 = 40 Bohr. # # written by Thomas L. Gibson November 09, 2011 ############################################################################################# ######Normalization Constants c1 = 0.21820330 c2 = 0.21815880 c3 = 0.21808216 c4 = 0.21796927 ######Wave Numbers k1 = 0.07479650 k2 = 0.14957282 k3 = 0.22430781 k4 = 0.29897818 ######Exponential Damping Coefficients kappa1 = 0.99719882 kappa2 = 0.98875071 kappa3 = 0.97451834 kappa4 = 0.95425995 ######Well Height and Width V0 = 0.5 L0 = 40 ############################################################################################ f(x) = (abs(x) >= 0.5*L0) ? V0 : 0 Y1L(x) = (x <= -0.5*L0) ? c1 * cos(k1*0.5*L0)*exp(0.5*kappa1*L0)*exp(kappa1*x): 1/0 Y1C(x) = (abs(x) <= 0.5*L0) ? c1*cos(k1*x) : 1/0 Y1R(x) = (x >= 0.5*L0) ? c1 * cos(k1*0.5*L0)*exp(0.5*kappa1*L0)*exp(-kappa1*x): 1/0 Y2L(x) = (x <= -0.5*L0) ? -c2 * sin(k2*0.5*L0)*exp(0.5*kappa2*L0)*exp(kappa2*x): 1/0 Y2C(x) = (abs(x) <= 0.5*L0) ? c2*sin(k2*x) : 1/0 Y2R(x) = (x >= 0.5*L0) ? c2 * sin(k2*0.5*L0)*exp(0.5*kappa2*L0)*exp(-kappa2*x): 1/0 Y3L(x) = (x <= -0.5*L0) ? c3 * cos(k3*0.5*L0)*exp(0.5*kappa3*L0)*exp(kappa3*x): 1/0 Y3C(x) = (abs(x) <= 0.5*L0) ? c3*cos(k3*x) : 1/0 Y3R(x) = (x >= 0.5*L0) ? c1 * cos(k3*0.5*L0)*exp(0.5*kappa3*L0)*exp(-kappa3*x): 1/0 Y4L(x) = (x <= -0.5*L0) ? -c4 * sin(k4*0.5*L0)*exp(0.5*kappa4*L0)*exp(kappa4*x): 1/0 Y4C(x) = (abs(x) <= 0.5*L0) ? c4*sin(k4*x) : 1/0 Y4R(x) = (x >= 0.5*L0) ? c4 * sin(k4*0.5*L0)*exp(0.5*kappa4*L0)*exp(-kappa4*x): 1/0 #set nokey set key top center set title "Finite Well: V0 = 0.5 Hartrees; L0 = 40 Bohr" plot [-L0: L0] [-0.25: V0 + 0.25] f(x) t 'V(x)' lw 3 lc rgb 'black',\ Y1L(x) t 'Y1' lw 2 lt 1 lc rgb 'red',\ Y1C(x) t ''lw 2 lt 1 lc rgb 'red',\ Y1R(x) t ''lw 2 lt 1 lc rgb 'red',\ Y2L(x) t 'Y2' lw 2 lt 3 lc rgb 'blue',\ Y2C(x) t '' lw 2 lt 3 lc rgb 'blue',\ Y2R(x) t '' lw 2 lt 3 lc rgb 'blue',\ Y3L(x) t 'Y3' lw 2 lt 5 lc rgb 'green',\ Y3C(x) t '' lw 2 lt 5 lc rgb 'green',\ Y3R(x) t '' lw 2 lt 5 lc rgb 'green',\ Y4L(x) t 'Y4' lw 2 lt 7 lc rgb 'orange',\ Y4C(x) t '' lw 2 lt 7 lc rgb 'orange',\ Y4R(x) t '' lw 2 lt 7 lc rgb 'orange' set xlabel "x (Bohr)" pause -1 "Hit return to make finite_well.ps or cntl c to exit." #z(x) = 0 set terminal postscript enhanced set output "finite_well.ps" #set nokey set key top center set title "Finite Well: V_{0} = 0.5 Hartrees; L_{0} = 40 Bohr" plot [-L0: L0] [-0.25: V0 + 0.25] f(x) t 'V(x)' lw 3 lc rgb 'black',\ Y1L(x) t '{/Symbol y}_{1}' lw 2 lt 1 lc rgb 'red',\ Y1C(x) t ''lw 2 lt 1 lc rgb 'red',\ Y1R(x) t ''lw 2 lt 1 lc rgb 'red',\ Y2L(x) t '{/Symbol y}_{2}' lw 2 lt 3 lc rgb 'blue',\ Y2C(x) t '' lw 2 lt 3 lc rgb 'blue',\ Y2R(x) t '' lw 2 lt 3 lc rgb 'blue',\ Y3L(x) t '{/Symbol y}_{3}' lw 2 lt 5 lc rgb 'green',\ Y3C(x) t '' lw 2 lt 5 lc rgb 'green',\ Y3R(x) t '' lw 2 lt 5 lc rgb 'green',\ Y4L(x) t '{/Symbol y}_{4}' lw 2 lt 7 lc rgb 'orange',\ Y4C(x) t '' lw 2 lt 7 lc rgb 'orange',\ Y4R(x) t '' lw 2 lt 7 lc rgb 'orange' set xlabel "x (Bohr)" reset exit