Wave function in a hydrogen atom : normalization

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SUMMARY

The discussion focuses on the normalization of the wave function in a hydrogen atom, specifically the expression Ψ(r,θ,Φ) = A(x+iy)e^{-r/2a_0}. The correct normalization constant A is determined to be A = -1/(a_0 √(8π))(1/(2a_0))^{3/2}. The integration limits for θ are clarified to be from 0 to π, correcting the initial assumption that θ ranges from -π to π. This adjustment is crucial for correctly evaluating the integral of sin³(θ), which results in a value of 4/3 when properly computed.

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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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