HIGHER PHYSICAL CHEMISTRY

The course has as its primary objective the learning and understanding of the main condensed phase transition processes, their properties and the quantitative and semi-quantitative parameters used for their description and prediction.

In more detail, the objectives of the course are:

- as regards knowledge and understanding, the objective is to understand the chemical-physical laws and quantities that govern the transition processes of condensed phases and their properties.

- with regards to the ability to apply knowledge and understanding, students must be able to apply the knowledge acquired to processes of manipulation of complex chemical systems of relevance in the field of advanced functional materials, in the field of health applications, in the environmental and energy fields. Applied systems with vast social impact are nanometric and small cluster systems, "responsive stimuli" systems, "programmable" multiphase systems, with functional properties that can be modulated over time, polymeric gels, etc...

- as regards autonomy of judgement, the objective is to make students capable of autonomously evaluating the relevance and applicability of the different phenomena and properties described in the different application fields, learning to independently and critically evaluate the relevance of the technological options available with respect to actual effectiveness.

- as regards the ability to communicate, the objective is to enable the student to communicate scientific topics with accuracy and rigor with particular reference to the field of condensed phases

- as regards the ability to continue the study independently, the objective is to enable the student to apply the concepts learned during the course to the understanding of phenomena and processes of specific interest

 The course will take place through lectures (5 ECTS) and classroom exercises (1 ECTS).

- Basic notions of differential and integral calculus: field of existence of a function, derivatives, definite and indefinite integrals, series and series expansions, simple differential equations of the first and second order

- Properties of thermodynamic functionals: Helmholtz and Gibbs free energy, entropy, internal energy and main thermodynamic relations

- Basic notions of intermolecular interaction potentials.

Attendance, as per the course regulations, is mandatory and must amount to at least 70% of the total hours.

Surface tension

Thermodynamic and mechanical definitions of surface tension. Molecular origin of surface tension. Dependence of surface tension on composition and temperature. Gibbs adsorption equation. Surfactant molecules. Specific processes driven by surface tension: Ostwald ripening and capillary condensation.

Transport processes

Thermodynamic interpretation of diffusion. Fick's first law. Concentration profile and its effect on diffusion. Fick's second law.

Phase transitions in condensed molecular systems

Basic concepts on phase transitions. Miscibility transitions in liquid systems: Free energy of mixing, curvature of the free energy function and phase separations. Stable and metastable systems. Flory parameter. Interfaces between phases and interfacial tension. Phase separation mechanisms: spinodal decomposition processes. Homogeneous and heterogeneous nucleation processes.

Liquid-solid phase transitions. Sub-cooling and solidification processes. Liquid-crystal phase transitions. Processes and mechanisms of homogeneous and heterogeneous nucleation in liquid-solid transitions. Kinetics, energy barriers and critical nucleation radii.

First and second order transitions. Entropy and relaxation modes: glass transitions. Arrhenius and non-Arrhenius relaxation regimes. Relaxation times from vibrational modes and configurational entropy modes. Kinetic phase transitions and relaxation models of glassy systems. Free volume models: Fox-Flory and William-Landel-Ferry. Cooperative models: Gibbs-Di Marzio, Adam-Gibbs. Regions of cooperative reorganization, Energy barriers

Polymer physical chemistry

Polymer chain flexibility, carrier and end-to-end distance. Models of ideal and real chains. Entropic elasticity. Polymeric solutions and volume excluded. Polymeric gels and networks. Stimuli-responsive polymers. Phase separation in polymer blends. Phase separation in block copolymers. Semi-crystalline polymers. Melting and glass transition. Simple models of viscoelastic response in polymeric systems: "entanglement" and "reptation".

Soft systems

Intermolecular forces, energy, spatial dimensions and response times in condensed phase. Phenomenological aspects of the response of complex systems to stimuli. Stress-strain relationships and constitutive equation as a function of time. Simple mechanical models: Voigt and Maxwell models. Maxwell relation and applications. Viscoelasticity and relaxation times: single molecule mechanism and Eyring hypothesis. Fluid transport processes: Newtonian and non-Newtonian fluids. Flow and viscosity in complex liquids. Viscoelasticity properties in complex fluids. Laminar motions and turbulent motions. Viscosity and flow. Pseudoplastic viscous fluids. Dilating fluids. Empirical flow equations. Viscoplastic fluids and Bingham fluids.

Polymer Physics (M. Rubinstein – Oxford University Press)

Soft Condensed Matter (R.A. Jones - OUP Oxford)

The Colloidal Domain (D. Fennel Evans, H. Wennerstroem - Wiley)

The exam consists of an oral test, covering exclusively the topics covered in class. Fundamental evaluation elements of the student's preparation are the correctness of the statements, the demonstrated understanding of the procedures for deriving the main results, the correctness of the equations discussed, the ownership of scientific language. The logical coherence of the concepts exposed and the ability to correlate theoretical formulations and experiments are considered further and desirable aspects of the validity of the preparation.

Definition and properties of soft matter systems.

Viscoelastic properties and relaxation times in soft materials.

Comparison between glass transitions and 1st order transitions.

Miscibility transitions in molecular systems and transition free energy

Phase separations: Spinodal decomposition processes and homogeneous nucleation processes

Homogeneous and heterogeneous nucleation mechanisms in liquid-solid transitions

Role of temperature in determining the stability of phase shifting systems.