67060 - Photochemistry and Supramolecular Chemestry

Course Unit Page

Academic Year 2018/2019

Learning outcomes

This course will provide to the the knowledge of the theoretical principles at the basis of photochemistry and supramolecular chemistry, particular enphasis will devoted to the possibile applications in the field of new materials

Course contents

Prerequisites: the student needs a solid knowledge of the general and inorganic chemistry and a basic knowledge of the chemical-physical principles at the basis of the electronic and vibrational properties of the polyatomic species.

 

Program:

Introduction : a brief discussion on the development of the photochemistry and of the supramolecular chemistry with examples of applications. Overview of the intermolecular forces. Introduction of the concept of supramolecular system and principle characteristics. 

Supramolecular chemistry : molecular recognition of cations, anions and molecules with different receptors. Chelating and templating effects (entropic and enthalpic components). Design of supramolecular systems: assembly and auto-assembly of biological and artificial systems. Supramolecular photochemistry. Overview on the possible applications of some supramolecular species.

Basis of the photo-physical and photochemical processes : excitation and deactivation of electronic exciting states, competition among these processes, kinetic constants, efficiencies, quantum yields. Lifetime of an electronic excited state: definition and correlation with the deactivation constants. Examples of emitting (and non-emitting) species and of their applications.

Molecular electronic states : brief hints of quantum mechanics. Orbitals, electronic configurations, electronic states of biatomic and polyatomic molecules (examples). Wave functions of molecules and Born-Oppenheimer approximation. Probability and selection rules for the electronic transitions in absorption; emission: radiative and non-radiative transitions. Franck-Condon principle. Jablonski diagram: approximations and useful information.

Spectrophotometry: block diagram of single and double ray spectrophotometers. Absorption spectra, brief discussion about the possible transitions in the organic molecules and in the metal complexes. Different methods of quantitative analysis based on electronic absorption.

Spectrofluorimetry: block diagram of a spectrofluorimeter. Emission and excitation spectra. Bimolecular quenching processes: Stern-Volmer equation; excimers and exciplexes. Photo energy transfer: columbic and exchange mechanisms. Applications. Photoelectron transfer:  redox potentials of electronic excited states. Examples of dynamic and static quenching.

Lifetime measurements : an overview on the different experimental techniques and instrumentation for the lifetime measurement of the electronic exciting states. Deeper discussion of the single photon counting technique.

Hints on luminescence anisotropy.

Metal and silica nanoparticles : hints on their synthesis and characterization, deeper discussion on their photophysical properties. Examples of their application as chemosensors and labels in the biological field. 

Electronic noses : theory and application.

Luminescent chemosensors and labels: theory and application.

Photodynamic and photothermal therapy: theory and application.

Absorption and emission properties of some common biomolecules.

Readings/Bibliography

The preparation of the exam will be centred on the slides of the lessons that will be available as pdf files in the dedicated university website (https://iol.unibo.it/).  
Only for the students that desire to go further in-depth in these topics I can suggest: for the photophysical part:

- A. Gilbert and J. Baggott, “Essentials of Molecular Photochemistry”, Blackwell, London, 1991

- L. Moggi, A. Juris and M. T. Gandolfi,"Il manuale del fotochimico", Bologna, Bononia University Press, 2006.

for the supramolecular chemistry part:

- J.W. Steed, J.L. Atwood, “Supramolecular Chemistry”, Wiley, New York, 2000

- J.-M. Lehn, “Supramolecular Chemistry - Concepts and Perspectives”, VCH, Weinheim, 1995

Teaching methods

The course consists only of lessons and there is no laboratory.

Assessment methods

Oral Exam

Teaching tools

PC, projector and board.

Office hours

See the website of Nelsi Zaccheroni