## Learning outcomes of the course unit

Knowledge: the aim of the course is to introduce the student to the basic knowledge of the crystalline solids, ranging from the symmetry of their periodic structures to the thermodynamics and kinetics of their formation and reactivity, from the radiation-matter interaction that originates the scattering process, to the most common diffraction techniques at the basis of their characterization.

Knowledge and applied comprehension: the course supplies the instruments to predict and to interpretate the behavior of solids as a function of the surrounding conditions and to characterize the solid state on the basis of the structural properties.

Learning ability: the course supplies the methodological instruments and the basic language of chemistry, allowing to deal with specific basic and advanced texts.

Communication ability: the student acquires the technical language that is necessary to communicate correctly complex arguments and to discuss with specialists.

Independent judgment: the student is stimulated to recognize connections among the treated arguments in order to develop an independent judgment ability based on the acquired skills.

## Course contents summary

The crystal state. Origin of 3D-periodicity. Crystallization. Nucleation and growth. Amorphous materials and glasses.

Bravais lattice and crystal lattice. Symmetry classification. Point symmetry. Point groups of Bravais lattices: the 7 crystallographic systems. Point group of crystal lattices: the 32 crystallographic classes. Symmetry operation involving translation. Space groups of crystal lattices.

X-rays. Scattering process: Thompson and Compton. Atomic scattering factor. Scattering from ordered systems: the diffraction process. Bragg's law and Laue's equations. Reciprocal lattice. Ewald sphere. Structure factor and equation of the electron density. Reletionships between diffraction and lattice simmetry. The phase problem in crystallography and its possible solution.

Practical aspects of X-ray diffraction. Single crystal and powder diffraction. Crystallographic data bases.

Classification of crystal structures. Close packing and eutactic models. Principal types of binary and ternary structures.

Polymorphysmus and phase transitions. Kinetic and thermodynamic classifications. Continuos phase transitions. Crystallographic trends in phase transitions.

Solid solutions: interstitial and substitutional. Heterovalent substitutions and charge compensation mechanisms.

Reactivity of solid. Solid state reactions. Principles and mechanisms.Experimental aspects. Sintering and ceramic materials.

## Recommended readings

A.R.West

Solid state chemistry and its applications

John Wiley & Sons Ltd., Chichester

lecture notes

## Teaching methods

lectures

## Assessment methods and criteria

oral examination