sp2 hybrid orbitals for n=2

dimensionless variables : 
	the variable r stands for r/2a.  Then:
	x = r sinθ cosϕ
	y = r sinθ sinϕ
	z = r cosθ
All functions and plots are evaluated at z = 0.
The prefactors are all set to 1.

Psi2s[x_,y_]:=(1-(Sqrt[x^2+y^2]))*Exp[-(Sqrt[x^2+y^2])]

Psi2px[x_,y_]:=x*Exp[-(Sqrt[x^2+y^2])]
Psi2py[x_,y_]:=y*Exp[-(Sqrt[x^2+y^2])]

ContourPlot[Psi2s[x,y],{x,-3,3},{y,-3,3}]

ContourPlot[(Psi2s[x,y])^2,{x,-3,3},{y,-3,3}]

ContourPlot[Psi2px[x,y],{x,-3,3},{y,-3,3}]

ContourPlot[(Psi2px[x,y])^2,{x,-3,3},{y,-3,3}]

ContourPlot[((Sqrt[1/3])*Psi2s[x,y]+(Sqrt[2/3])*Psi2py[x,y]),{x,-3,3},{y,-3,3}]

ContourPlot[((Sqrt[1/3])*Psi2s[x,y]+(Sqrt[2/3])*Psi2py[x,y])^2,{x,-3,3},{y,-3,3}]

ContourPlot[((Sqrt[1/3])*Psi2s[x,y]+(Sqrt[1/2])*Psi2px[x,y]-(Sqrt[1/6])*Psi2py[x,y])^2,{x,-3,3},{y,-3,3}]

ContourPlot[((Sqrt[1/3])*Psi2s[x,y]-(Sqrt[1/2])*Psi2px[x,y]-(Sqrt[1/6])*Psi2py[x,y])^2,{x,-3,3},{y,-3,3}]