Physical Chemistry B

A.Y. 2021/2022
9
Max ECTS
96
Overall hours
SSD
CHIM/02
Language
Italian
Learning objectives
The course provides a systematic exposition of basic concepts of the solid state of matter and of its properties. The aim is to provide a solid ground for the understanding of the vast and varied phenomenology that accompanies the matter at the solid state, one that can be of help to rationalize the structural, microstructural, thermal, optical and transport properties of materials.
Expected learning outcomes
Students will master electronic band structures and their relation with optical and transport phenomena. They will gain comprehension of phase diagrams, phase transition, reactivity and defects thermodynamics in the solid state; and a theoretical and practical knowledge of the following experimental techniques: XRPD, SEM/EMPA, TEM/EELS, AFM, EPR, EIS, UV, DSC.
Course syllabus and organization

Single session

Responsible
Lectures will be given in synchronous mode with the help of a meeting Teams. Lectures will not be recorded but student can find in Ariel .mp4 files of the past years, along with all the ancillary material typically provided with the course (slides, notes and explanations as .pdf files). By the same token, in the case of epidemic threat, the written examination will be performed on-line, on exam.net, with the help of a Zoom meeting. The oral examination will be performed via a meeting Zoom or Microsoft Teams.
Course syllabus
Simple models of metals. Drude model: DC and AC conductivity, magnetotransport and Hall effect, thermal conductivity, thermopower. Sommerfield model: Fermi sphere, density of states; energy, pressure and entropy of the free-electron quantum gas. Fermi-Dirac statistics: gran-canonical parition function, Fermi function, Sommerfield expansion.

Crystal structure. Lattices, basis vectors and unit cells. Bravais lattices. Reciprocal lattice. Lattice planes, Miller indices. Investigation of crystal structures: Thomson diffusion, X ray diffraction, von Laue vs. Bragg laws, structure factor.

Electrons in periodic potentials. Bloch theorem, Bloch functions, energy bands. Tight-binding method and application to model systems: linear chains, two- and three-dimensional materials. Peirls distortion. Graphene electronic structure: Dirac cones, chiral fermions.

Semiclassical electron dynamics. Wavapackects, uncertainty principle, semiclassical equations of motion, phase-space distribution function. Fundamental properties: inertness of filled bands, electrons and holes, effective mass tensor. Drude-Boltzmann theory of DC and AC charge transport. Optical conductivity. Diffusive vs. balistic motion. Disordered systems.

Semiconductors. Number density of charge carriers in thermal equilibrium, law of mass action, chemical potential. Electron and hole doping. Heterogeneous semiconductors: p-n junction, potential profile, current. Interfaces: metal/semiconductor, semiconductor heterostructures, quantum wells. Delta doping and remote doping. Two-dimensional electron-gases and electrostatic gating. Surfaces and Fermi level pinning.

Phonons. Normal modes, statistical mechanics of harmonic oscillators. Phonon dispersion curves, acoustic and optical phonons. Phonon heat capacitances, Einstein and Debye models. Lattice thermal conductivity, phonon-phonon scattering.

Phase diagrams: one components systems; two components systems with intermediate phases and solid solutions; phase transition by the structural, thermodynamic kinetical point of view.

Defects in solids and reactivity. Point defects in solids; mass and charge diffusion mechanisms. Reactivity at the solid phase.

Experimental Techniques: XRPD, SEM/EMPA, TEM/EELS, AFM, EPR, IS, UV, DSC.
Prerequisites for admission
"Chimica Quantistica" and "Metodi matematici applicati alla chimica" (or similar courses covering basic quantum mechanics and math) are strongly recommended.
Teaching methods
The course is organized through a series of lectures on blackboard. The laboratory experiences will be carried out both in the student's labs and in research labs where the instruments are positioned.
Teaching Resources
Textbooks:

- N. W. Ashcroft and D. N. Mermim, Solid State Physics, Saunders College Publishing
- T. Ihn, Semiconductor Nanostructures, Oxford University Press,
- Anthony R. West, Solid State Chemistry and its applications Wiley India

Further supporting material (lecture notes) will be provided to the students upon request.
Assessment methods and Criteria
Access to the final exam is subjected to the compilation of a short report on the experimental activities performed in the laboratory. The examination is written, 3 hours long, and consists of two open questions on topics discussed in classroom lectures, and two simple exercises aimed at establishing the degree of understanding of the course. The written part is followed by a critical oral discussion of the experimental report.
CHIM/02 - PHYSICAL CHEMISTRY - University credits: 9
Practicals: 16 hours
Laboratories: 32 hours
Lessons: 48 hours
Educational website(s)