Introductory Quantum Mechanics I

Illustration of an avoided crossing.

The Born-Oppenheimer approximation fails when two electron states almost cross, also known as an "avoided crossing." An avoided crossing is illustrated in the above plot of adiabatic electronic energy as a function of R. (Figure by Prof. Troy Van Voorhis.)


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Fall 2005



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Course Description

5.73 covers fundamental concepts of quantum mechanics: wave properties, uncertainty principles, Schrödinger equation, and operator and matrix methods. Basic applications of the following are discussed: one-dimensional potentials (harmonic oscillator), three-dimensional centrosymmetric potentials (hydrogen atom), and angular momentum and spin. The course also examines approximation methods: variational principle and perturbation theory.

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Troy Van Voorhis. 5.73 Introductory Quantum Mechanics I. Fall 2005. Massachusetts Institute of Technology: MIT OpenCourseWare, License: Creative Commons BY-NC-SA.

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