Spectroscopic Techniques


During the UC the students will develop transversal knowledge and skills allowing to:
• Improve the knowledge acquired during previous courses;
• Develop communication skills, to elaborate concise and coherent argumentation, both oral and in writing; develop team-work capabilities;
• Develop research competencies as well as aptitude for the interpretation of scientific literature.

By accomplishing this UC the students will have developed scientific knowledge and know-how in order to:
• Undertake informed decisions on which spectroscopic technique is suitable for the resolution of a given challenge, to investigate the fundamental properties of a particular material.
• Adequately process the retrieved spectral data and carry out spectral interpretation
• Interpret the obtained results taking into account the basic principles of Atomic and Molecular Physics in order to identify the origin of the observed transitions and energy levels involved; Interpret the shape and intensity of the observed signal and gather information relevant to the problem in hands.

General characterization





Responsible teacher

António Alberto Dias


Weekly - 2

Total - 29

Teaching language



It is highly recommended the previous approval in the following courses: Ótica, Física Atómica (e Física Molecular) e Mecânica Quântica.


• Modern Spectroscopy 4th Ed. (Wiley), J.M. Hollas, 2004
• Molecular Spectroscopy, Jeanne L. McHale, CRC Press, 2017.
• Atomic and molecular spectroscopy: basic aspects and practical applications, S. Svanberg, Springer, 2004.
• Molecular Quantum Mechanics, 4th ed., P.W. Atkins, R. S. Friedman, Oxford University Press, 2005
• Atoms and Molecules, M. Weissbluth, Academic Press, 1978.
• Optical Spectroscopy: Methods and Instrumentations, Nikolai V. Tkachenko, Elsevier Science, 2006. 
• Electronic and photoelectron spectroscopy - Fundamentals and case studies, Andrew M. Ellis, Miklos Feher, Timothy G. Wrigh, Cambridge University Press, 2005.
• Artigos científicos a especificar durante as aulas.

Teaching method

This curricular unit is organized in two hours of theoretical-practical classes (TP) per week. These classes are expository involving the use of audiovisual media, in which will be presented the various spectroscopy techniques, including examples of application, which will be complemented by discussion of concrete problems. Students are encouraged to a committed study of the subjects covered and are expected to maintain regular contact with teachers outside of school hours.

During the semester, there will be several laboratory classes, in which they will have direct contact with some of the equipment covered in this UC, will perform practical work and produce the respective report.

There will be a seminar on spectroscopic techniques or methods and at the end of the semester will have an individual assessment in the form of a test.

During the semester will be valued active participation in classes

Evaluation method

Continuous assessment of knowledge (see details in portuguese)

Subject matter

  1. Introduction

Brief historical perspective; Considerations on Optics, Atomic (and Molecular) physics and Quantum Mechanics; Applications of Modern spectroscopy

  1. Interaction of electromagnetic radiation and matter

Electromagnetic radiation. Main interactions. Radiation emission and absorption processes. Probability and width of transition. Electric dipole operator. Connection with experimental results.


3. Atomic and Molecular spectroscopy

The Hydrogen atom. Multi-electron atoms and molecules. Key results and spectroscopic notation.


4. Techniques and equipments used in spectroscopy

Sources of radiation, detectors, monochromators and interferometers, features of optic components (lenses, mirrors, windows, collimators, etc.) Reflection absorption and transmission spectroscopies. Beer-Lambert law. Experimental features that influence the intensity and width of spectral bands. Signal-to-noise ratio and resolving power of the spectrometer. Handling of optic components.

5. X-Ray Fluorescence spectroscopy (XRF)

Production of X-Rays. X-ray Fluorescence. Components of an XRF spectrometer. Interpretation and quantification of XRF spectra. Practical application.

6. Vibrational spectroscopy – Infrared and Raman

Molecular vibrations and transition rules. Normal modes of vibration. Identification of IR active modes. Anharmocity of the harmonic oscillator. Interpretation of IR spectra.

Raman scattering. Classical approach to the Raman effect. The polarizability tensor and symmetry properties. Selection rules. Polarization of transitions. Practical application.

7. Ultraviolet photoelectron spectroscopy

Radiation sources, energy analyzer, detection and signal processing. Types of spectra. Direct ionization and self-ionization. Ressonant absorption and decay. Franck Condon factor. Angular distribution of photoelectrons. Electric  dipole selection rules. Practical application