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Particle in a Box Problem

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Derivation of the Schrödinger equation

 

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Derivation of the Schrödinger equation

 

 

 

 

 

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Derivation of the Schrödinger equation

 

 

 

 

 

 

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Derivation of the Schrödinger equation

 

 

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Derivation of the Schrödinger equation

 

 

 

 

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Derivation of the Schrödinger equation

 

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Solution to the Schrödinger Equation

The solutions to the Schrödinger equation are called wave functions. A wave function gives a complete description of any system.

The time-independent Schrödinger equation can be solved analytically only in a few special cases such as:

    • The Particle in a Box
    • The Harmonic Oscillator
    • The Rigid Rotor
    • The Hydrogen Atom

In this next section we will discuss the solution of the Schrödinger equation for particle in a box. The remaining cases will be discussed later throughout the course.

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Particle in a One-Dimensional Box

 

 

The potential energy out side this space is set to infinity. Now the conditions of the potential energy of the particle are summarized as

 

 

 

 

 

 

 

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

 

 

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Particle in a One-Dimensional Box

 

 

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Particle in a One-Dimensional Box

 

 

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Particle in a One-Dimensional Box

 

 

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Particle in a One-Dimensional Box

 

 

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Particle in a One-Dimensional Box

 

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

Energy and wave function of a particle in a box

For a particle moving in a one dimensional box, we have shown that

and

We noticed from the graph that:

 

 

 

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  1. The orthogonality of the wave functions is clear. From the figure we can see that

 

 

 

 

Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

 

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Particle in a One-Dimensional Box

Correspondence principle

 

The probability distribution of a particle in a box.

 

 

 

 

 

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Particle in a One-Dimensional Box

 

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Particle in a One-Dimensional Box

 

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Postulates of Quantum Mechanics

 

 

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