- #1
ani4physics
- 29
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Hi all. Just have a quick question on perturbation theory. Let's consider a molecule in ground electronic state. If a time-independent external perturbation acts on the molecule, the average electronic energy is going to change. From time-independent perturbation theory, we know that
<E> = E(0) + lambda . E(1) + (lamdba)^2 . E(2) + ...
Where lambda is the external parameter which determines the strength of the perturbation. E(0) is the unperturbed energy of teh ground state. If we substract E(0) from <E>, we get,
delta E = lambda . E(1) + (lamdba)^2 . E(2) + ...
Now my question is: when the perturbation acts, the net energy change of the molecule is delta E. If we consider the external perturbation as "an external force", can we interpret delta E as the net work done by the external force on the molecule?
Please let me know if this interpretation is correct. Happy holidays to everyone.
<E> = E(0) + lambda . E(1) + (lamdba)^2 . E(2) + ...
Where lambda is the external parameter which determines the strength of the perturbation. E(0) is the unperturbed energy of teh ground state. If we substract E(0) from <E>, we get,
delta E = lambda . E(1) + (lamdba)^2 . E(2) + ...
Now my question is: when the perturbation acts, the net energy change of the molecule is delta E. If we consider the external perturbation as "an external force", can we interpret delta E as the net work done by the external force on the molecule?
Please let me know if this interpretation is correct. Happy holidays to everyone.