EDIT: Sorry... I have to use perturbation theory. My mistake.(adsbygoogle = window.adsbygoogle || []).push({});

Hey... I have a quick question. I have to calculate the approximate change in energy via variation theory when the 'error' Hamiltonian for the Stark effect is defined as: [tex]|\vec{E}|cos\theta\bullet eR[/tex]

If I'm not mistaken, the change in energy of the 1s orbital of a hydrogen atom will be:

<E>=k[tex]\int r^3e^{-2r/a}dr \int sin\theta cos\theta d\theta \int d\varphi[/tex]

However, the middle integral becomes 0 when the limits of 0 and pi are plugged in. This doesn't seem right. Am I doing anything incorrectly?

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# Stark Effect using first order variation theory.

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