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[http://www.falstad.com/qmatom/ 3D H atom orbital viewer]<br> | [http://www.falstad.com/qmatom/ 3D H atom orbital viewer]<br> | ||

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Instructor: Dr. [Sabieh Anwar] *Office hours:* Monday, (2-6 pm); Friday, (3-5 pm)

Teaching Fellows: [Shahid Sattar] *Office hours:*
Wednesday(12-3 pm), Thursday(12-3 pm) and [Shama Rashid] *Office hours:* Monday, Tuesday and Thursday (3-5 pm)

Textbook: *Quantum Physics of Atoms, Molecules, Solids, Nuclei and Particles* by R. Eisberg and R. Resnick. (The book is available in the library for Rs. 1100.)

**Week 1**

- Blackbody radiation
- Spectral radiance (experimental results); Stefan's and Wien's displacement law
- Density of modes and average energies using principle of equipartition of energy
- Rayleigh-Jeans formula
- Planck's correction
- Energy is quantized!

**Week 2**

- Particle nature of electromagnetic radiation
- The photoelectric effect
- Compton Scattering
- What are X-rays?
- Pair production and Pair annihilation
- Light:particles or waves?

**Week 3**

- Wave-particle duality and de Broglie relationship
- Electron diffraction and interference (some original experiments)
- Matter waves and wave packets
- Relationship between position and momentum spaces and origins of Uncertainty principle

**Week 4**

- Uncertainty principle (position and momentum; energy and time)
- Atomic spectroscopy and lifetime broadening
- Bohr's model
- The concept of reduced mass
- Sommerfeld and Wilson's quantization

**Weeks 5 and 6**

- Motivation for the Schrodinger Equation
- Wavefunction and its probabilistic interpretation
- Expectation values, legitimate definition
- Corresponding principle
- Time independent Schrodinger Equation
- Solving the Schrodinger Equation for a free particle

**Week 7**

- Acceptable solutions of the Schrodinger Equation; legitimate wavefunctions
- Particle in an infinite well

**Week 8** (This weak is devoted to revisions and addressing misconceptions)

- How do electrons get across nodes? Explanation This is not an easy question to answer. The simplest answer to the question is to stop thinking of the electron as a classical point particle behaving like a sphere. Rather, the best and the only way to describe the electron is through its wavefunction spread out in space. Then everything follows from there. I will discuss this further in the class.

**Weeks 9 and 10**

- Particle in a finite well (do-it-yourself)
- Step potential when energy is less than the potential height
- Step potential when energy is greater than the potential height
- Barrier potential, quantum mechanical tunneling, reflectivity and transmittivity
- Ramseur effect, size resonance
- Analogies with optics:
- reflectivity from a dielectric
- total internal reflection and evanescent waves
- frustrated total internal reflection

- Scanning tunneling microscopy
- Schottky barrier
- Field emission: metal placed in an electric field

**Week 11**

- The H atom
- Solving the three dimensional Schrodinger equation for a spherical potential
- Origin of principal, azimuthal and orbital quantum numbers
- orbitals: s, p, d and f
- full derivation of spherical harmonic functions as solutions of the polar part of Schrodinger's equation

**Weeks 12 and 13**

- Orbitals continued
- Degeneracy and symmetry considerations for the free H atom
- Radial wavefunction
- radial probability density

**Week 14**

- angular momentum in quantum mechanics
- space quantization
- significance of the quantum numbers, n, l and m_l