I have a quantum problem that I can't seem to figure out:(adsbygoogle = window.adsbygoogle || []).push({});

There's an electron in a 1-D rigid box of length 2A but it is known to reside in a central segment of 1A with uniform probability of residing within this segment.

There are two possible wavefunctions:

one with constant phase: ψ(x)= 1/√a (a=1A)

and with varying phase: ψ(x)= e^(jxpi/4a)/√a

Both of those wave equations are for within the segment and outside the segment ψ(x)= 0.

Determine the 3 lowest energies expected for each case and the probability of each outcome.

Since the wave equation is 0 outside the segment, I thought I'd treat this as a regular particle in a box problem with the box of length 1A. Then I plugged the ψ(x) given into the Schrodinger's equation to find E for the 2 cases:

d^2/dx^2 ψ(x) = -(2m/h^2)*E*ψ(x)

However, for the first case of constant phase, this gives that E=0 and for the second case, E= (h*pi)^2/(32ma^2) which is really just a constant and I can't get the 3 lowest energies.

What am I doing wrong? Any help would be appreciated!

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# Quantum particle in a rigid box with 2 given wavefunctions solving for energies

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