CODE  61736 

ACADEMIC YEAR  2022/2023 
CREDITS 

SCIENTIFIC DISCIPLINARY SECTOR  FIS/03 
LANGUAGE  Italian 
TEACHING LOCATION 

SEMESTER  2° Semester 
PREREQUISITES 
Prerequisites
You can take the exam for this unit if you passed the following exam(s):

TEACHING MATERIALS  AULAWEB 
This is a basic course of classical and quantum statistical physics, with applications to gases, liquids and solids.
Basic knowledge about the principles of statisticall mechanics. Basic knowledge about the physical properties of gases, liquids and solids. Ability to solve simple exercises about the different topics of the course.
Standard lectures and exercises.
Quotations of thermodynamics Classical Statistical Mechanics  Phase space. Macrostates and microstates. Liouville equation. Statistical ensembles. Microcanonical ensemble. Entropy and temperature in the microcanonical ensemble. Counting microstates and the Gibbs Paradox. Ideal gas equation and internal energy. Canonical ensemble. Partition function and its relationship with Hehlmoltz free energy. Energy fluctuations and thermal capacity. Energy equipartition theorem. Examples of partition functions: harmonic oscillator, rigid rotator, ideal gas. Law of Dulong and Petit. Quantum statistical mechanics  Density matrix. Microcanonical ensemble. Canonical ensemble. Partition function of the harmonic oscillator and of the quantum rigid rotator. Einstein model for the specific heat of the solids. Particle with spin 1/2. Grancanonical ensemble. Density fluctuations and isothermal compressibility. Quantum perfect gas (monoatomic)  BoseEinstein and FermiDirac statistics. Density of states in energy. Classical limit: the ideal gas. Strongly degenerate Bose gas and BoseEinstein condensation. Strongly degenerate Fermi gas and electronic specific heat of metals. Weakly degenerate perfect gas. Photon gas and black body radiation. Perfect Polyatomic Gases  BornOppenheimer approximation. Biatomic molecules: translational, vibrational and rotational partition functions. Heteronuclear biatomic molecules. Homonuclear biatomic molecules: ortho and parahydrogen. Examples of triatomic molecules. Crystal Lattices  Bravais lattices and crystals. Primitive and conventional unit cells. WignerSeitz cell. Reciprocal lattice and first Brillouin zone. Examples of 2D and 3D crystal lattices. Lattice vibrations in Solids  Small oscillations of a linear chain with one atom per cell. Normal vibrational modes of a crystal: general treatment. Example: linear chain with two atoms per cell. Phonons. Vibrational free energy of a solid. Thermal capacity of a solid in Debye approximation. Lattice vibrations of threedimensional solids and measurement of dispersion curves. Interacting gases and liquds  Pair correlation function g(r) and potential of the mean force. Calculation of pressure and g(r) for a diluted interacting gas by the virial expansion.
Lecture notes.
Office hours: Every day after appointment request.
RICCARDO FERRANDO (President)
DAVIDE BOCHICCHIO
CORRADO BORAGNO
FRANCESCO BUATIER DE MONGEOT
GIULIA ROSSI (President Substitute)
All class schedules are posted on the EasyAcademy portal.
The student must be able to carry out simple exercises and to develop independently and critically the topics covered by the course. This is ascertained by evaluating the performance of the exercises in the written exam and the quality of the oral exam, where the knowledge of the fundamental concepts from the theoretical point of view and the knowledge of the correct orders of magnitude of the quantities that characterize the phenomena are verified.