Crystal bonding. Elastic and plastic deformation- Hooke’s law. Failure of the static model. Lattice vibrations. Phonons. Energy density in lattice. Exact theory of molecular heat. Optical properties of lattice in the infrared. Ionic crystals. The non-armonic approach.

Origin of energy bands. Electron wavefunctions in periodic potential. Nearly free electron theory approximation. The tight – binding approximation. Metals-insulators- semiconductors. Density of states. Fermi surface. Bloch electron. Effective mass. Holes. Experimental determination of energy bands. Structure of energy bands in semiconductors. Carrier concentration in doped semiconductors – in compensated semiconductors. Electric conductivity of semiconductors- mobility. Carrier scattering mechanisms. Hall effect in semiconductors.

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2. Fundamental systems. Symmetries, rotations and the quantum description of angular momentum, composition of angular momenta, Glebsch-Gordan coefficients, Schrodinger equations in three dimensions for different potentials, interaction of particles with the EM field, particles with spin.

3. Composite systems. The quantum description of composite systems, fermions and bosons, Pauli’s exclusion principle, Fermi gas.

4. Techniques and applications. Perturbation theory, the variational method, mean field theory. Applications to atomic systems (the real hydrogen atom, helium atom, Stark and Zeeman effects, orbital theory and the periodic table, Thomas-Fermi theory).

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Classical approach of emission of radiation.

Schrodinger equation and the Hydrogen atom.

Transitions between energy states and emission of radiation. Quantum approach of radiating dipoles – Electric dipole transitions and higher order transitions. Average lifetime of atoms on an excited state. Linewidth and shape of spectral lines. Natural linewidth and reasons for its broadening.

The shell model and alkali atoms. Central field approximation. Periodic table. Active potentials.

Fine structure. Spit-orbit interaction. Total (spin and orbital) angular momentum (J).

LS (orbital and spin angular momentum) coupling. JJ coupling. Hyper fine structure.

Influence of external fiels on atoms. Zeeman, Paschen-Back & Stark effects. Examples.

Μolecular Physics:

I. Theory of chemical bond

Αdiabatic (Born-Oppenheimer) approximation. Hellman – Feynman theorem. Virial theorem.

Introduction to the quantum mechanical theory of the chemical bond. Ion of hydrogen molecule (H2+). Hydrogen molecule (H2). Heitler – London (Valence bond) theory and molecular orbital (MO) theory. Homonuclear diatomic molecules. Covalent bonding. Electrons in an axially symmetric field. Description of diatomic molecules with the molecular orbital and the valence bond theories. Symbolism of states of diatomic molecules. Total angular momentum of electrons. Heteronuclear diatomic molecules. Ionic bonding. Polyatomic molecules – Stater determinant. Hybridization of atomic orbitals. Conjugated molecules. Hydrogen bonding. Van der Waals interactions. London dispersion forces.

II. Molecular spectra

Rotation and vibration of diatomic molecules. Rotational spectra. Vibrational spectra. Rotational – vibrational spectra. Vibration modes of polyatomic molecules. Raman spectra. Molecular electronic states. Electronic spectra due to transitions between different electronic states. Franck – Condon principle. Excited state decay with emission of radiation. Ionization energy and electron affinity.

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