Wave function in a hydrogen atom : normalization

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The discussion revolves around normalizing the wave function of a hydrogen atom, specifically Ψ(r,θ,Φ) = A(x+iy)e^{-r/2a_0}. The provided answer for the normalization constant A is -1/(a_0√(8π))(1/(2a_0))^{3/2}. A critical point raised is the incorrect integration limits for θ, which should range from 0 to π instead of -π to π, affecting the integral of sin^3(θ). The correct evaluation of the integral from 0 to π yields 4/3, resolving the normalization issue. The conversation emphasizes the importance of proper variable limits in integration for accurate results.
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Homework Statement


Determined wave function in a hydrogen atom.
## Ψ(r,θ,Φ) = A(x+iy)e^{ \frac{-r}{2a_0}}## << find A by normalization

Answer of a question in my book is ## A = -\frac{1}{a_0 \sqrt{8 \pi}} (\frac{1}{2a_0})^{3/2} ##

Homework Equations


## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = \int \int \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) r^2 \sin (θ) drdθdΦ =1 ##
##x = r \sinθ \cos Φ ##
##y = r \sinθ \sin Φ##
##z = r \cosθ ##

The Attempt at a Solution


r [0→∞] ,θ[-##\pi##→##\pi##] ,Φ[0→##2 \pi##][/B]
## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = \int \int \int e^{ \frac{-r}{a_0}} r^2(\sin^2θ \cos^2Φ + \sin^2θ \sin^2Φ) r^2 \sin θ drdθdΦ##
## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = \int \int \int e^{ \frac{-r}{a_0}} r^4\sin^3θ drdθdΦ##
## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = 2\pi \int e^{ \frac{-r}{a_0}} r^4 dr \int \sin^3θ dθ##
## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = 2\pi a_0^5 4! \int \sin^3θ dθ##

## \int \sin^3θ dθ = 0 ## ; θ[-##\pi##→##\pi##] because ##sin^3θ## is odd function

## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = 0 ## My answer is wrong , please help
 
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Another said:
## \int \sin^3θ dθ = 0 ## ; θ[-##\pi##→##\pi##] because ##sin^3θ## is odd function

## \int Ψ^*(r,θ,Φ)Ψ(r,θ,Φ) d^3r = 0 ## My answer is wrong , please help

The angle ##\theta## doesn't go from 0 to ##2\pi##, it only goes from 0 to ##\pi##. To integrate ##sin^3(\theta)##, change variables by letting ##u = cos(\theta)##.
 
stevendaryl said:
The angle ##\theta## doesn't go from 0 to ##2\pi##, it only goes from 0 to ##\pi##. To integrate ##sin^3(\theta)##, change variables by letting ##u = cos(\theta)##.

##\int sin^3(\theta) d\theta ## from 0 to ##\pi## =## \frac{4}{3} ##

thank you very much. This is my mistake.
 

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