Master degree in Materials Science

Advanced Diffraction Methods for Applications

Advanced Diffraction Methods for Applications

Academic year 2021/2022

Sommario del corso

• Course objectives
• Results of learning outcomes
• Course delivery
• Learning assessment methods
• Support activities
• Program
• Suggested textbooks and readings
• Notes
• Teaching tools

Course objectives

After attending the course (theoretical lessons and laboratory sessions with practical activities), the student will be able to:

1. Describe the main applications of X-ray diffraction.
2. Describe the main instrumental configurations (laboratory instruments) with particular attention to the optics, related aberrations, and their effect on the experimental data.
3. Recognize the main effects of the instrumental configuration on the quality of the diffraction pattern and, consequently, propose solutions to artifacts and improvements in the experimental setup.
4. Apply the knowledge acquired to Material Science issues

Results of learning outcomes

KNOWLEDGE AND UNDERSTANDING

The course aims to stimulate the student to understand the relationships between theoretical concepts of crystallography and diffraction and their experimental evidence. For this reason, the laboratory sessions will be an integral part of the course.

APPLYING KNOWLEDGE AND UNDERSTANDING

A didactic path is proposed that goes from understanding to applying the concepts learned to:

1. Diffractometric analysis techniques from powders with particular reference to the theoretical basis and their evidence in the lab.
2. Qualitative analysis of a powder diffraction pattern 
3. Crystal structure refinement (Rietveld method) on synthetic and natural materials using X-ray powder diffraction as a reference technique both in R&D and quality analysis laboratories
4. Quantitative analysis of mixtures of inorganic crystalline phases (included the amorphous fraction quantification)
5. Texture analysis
6. Line broadening analysis (grain size and microstrain)

Course delivery

Lectures and Laboratory

Online streaming @ https://unito.webex.com/meet/linda.pastero

The program addressed during classes will be thoroughly revisited during the laboratory sessions.

Learning assessment methods

The oral exam will discuss all the topics considered during the classes, starting from a practical case (indexing, refinement, or qualitative-quantitative analysis, texture, size/microstrain analysis).

Laboratory reports will be presented at the end of the course, and their relevance, completeness, and personal re-elaboration will be considered in the final assessment.

If not in attendance, candidates will take the exam orally on the Webex platform with screen sharing and active registration.

Support activities

The teacher is available by appointment to discuss, repeat, and clarify the concepts explained in class and the laboratory activities.

Program

Recap of crystallography: Crystalline systems and classes. Diffraction principles.

Diffraction from powders: Conventional sources, optics, and detectors. Parafocusing and transmission geometries. Notes on non-conventional sources.

Qualitative analysis: Identification of crystalline phases in polycrystalline mixtures. Databases. Use of the free QUALX program for phase identification in crystalline mixtures.

The Rietveld method: Quantitative, structural, and textural analysis. Use of structural refinement programs: an overview of the main structural refinement programs with particular reference to the free GSASII program. Notes on the indexing of crystalline phases.

The line broadening analysis: grain size and microstrain analysis with particular reference to the Williamson-Hall (W-H) method

Laboratory: Acquisition of data on laboratory instruments for research and routine analysis, with particular attention to the configurations of the optics and their effect on the experimental data. Notes on single-crystal diffraction.

Identification of crystalline phases in polycrystalline mixtures. Exercises on structural and quantitative analysis on X-ray powder patterns collected during the laboratory sessions: structural refinement of crystalline phases, multiphase mixtures, mixtures containing amorphous. Texture, grain size, and microstrain analysis on XRPD patterns collected during laboratory practices. Indexing of diffraction patterns. Pattern deconvolution and its crystallographic meaning 

Hammond - The Basics of Crystallography and Diffraction. IUCr-Oxford Science Publications

R.A. Young – The Rietveld method. Oxford Science Publication

V.K. Pecharsky, P.Y. Zavalij - Fundamentals of powder diffraction and structural characterization of materials. Springer

Class schedule

Note

Students are reminded of the prohibition of sharing and dissemination in any form of platform-loaded teaching materials and videoconferencing lessons: any action that violates this norm will be denounced by the teachers to the organs of the University and will be pursued according to the law.
In addition, the link to the videoconferencing lessons (Webex and the like) must be exclusively through the institutional e-mail and using their name and surname.

• Teaching materials
• Exams and finals
• Go to Moodle
• Visit the forums