Identical particles and degenrate energy levels

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SUMMARY

The discussion focuses on calculating the ground state energy of five non-interacting electrons in a three-dimensional harmonic oscillator potential, defined by the equation V(x,y,z) = (k/2)(x² + y² + z²). The energy levels are determined using the formula E_{n_x,n_y,n_z} = (n_x+n_y+n_z + 3/2)(ħω/2). It is established that while at most two electrons can occupy the same quantum state, multiple electrons can share the same energy level as long as they have different quantum numbers. The correct ground state energy configuration is identified as E = 2E_{000} + 2E_{100} + E_{010}.

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  • Understanding of quantum mechanics, specifically the principles of quantum states and degeneracy.
  • Familiarity with the three-dimensional harmonic oscillator potential.
  • Knowledge of energy quantization in quantum systems.
  • Basic grasp of electron configuration and the Pauli exclusion principle.
NEXT STEPS
  • Study the implications of the Pauli exclusion principle in multi-electron systems.
  • Explore the concept of degeneracy in quantum mechanics and its applications.
  • Learn about the mathematical derivation of energy levels in harmonic oscillators.
  • Investigate the role of quantum numbers in determining electron states in quantum systems.
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Students and professionals in physics, particularly those specializing in quantum mechanics, as well as researchers interested in the behavior of electrons in potential fields.

Sunshine
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Homework Statement


Five electrons (with mass m) whose interaction can be neglected, are in the same 3-dim harmonic oscillatorpotential
V(x,y,z) = \frac k2 (x^2 + y^2 + z^2)

What is the ground state energy?

Homework Equations




The Attempt at a Solution



I have the energy for the potential. It is:
E_{n_x,n_y,n_z} = (n_x+n_y+n_z + \frac 32)\frac{\hbar\omega}2

My question is about the degeneracy.Since it's electrons, at most 2 of them can be in the same state, but can more than 2 electrons have the same energy?

Relating to this question: Should the ground state energy for this system be

E=2E_{111}+2E_{211}+E_{121}

or are the two states (211) and (121) not allowed to have more than 2 electrons totally, ie

E=2E_{111}+2E_{211}+E_{221}
 
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Sunshine said:

Homework Statement


Five electrons (with mass m) whose interaction can be neglected, are in the same 3-dim harmonic oscillatorpotential
V(x,y,z) = \frac k2 (x^2 + y^2 + z^2)

What is the ground state energy?

Homework Equations




The Attempt at a Solution



I have the energy for the potential. It is:
E_{n_x,n_y,n_z} = (n_x+n_y+n_z + \frac 32)\frac{\hbar\omega}2

My question is about the degeneracy.Since it's electrons, at most 2 of them can be in the same state, but can more than 2 electrons have the same energy?
of course. As long as they don't all have the same quantum numbers.
Relating to this question: Should the ground state energy for this system be

E=2E_{111}+2E_{211}+E_{121}

or are the two states (211) and (121) not allowed to have more than 2 electrons totally, ie

E=2E_{111}+2E_{211}+E_{221}

Wait. Why aren't you starting with the n=0 states??
 
Well, first of all, the n's can be zero ...

Yes, more than two electrons can have the same energy if they are in a different state.
The states are labeled by the values of nx, ny, and nz, so the states (211) and (121) are each allowed to have two electrons, for a total maximum of four.
 
Ok, didn't know that n could be 0. So the energy should be

2E_{000}+2E_{100}+E_{010}?
 

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