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Crystallography 2018
Structural Chemistry & Crystallography Communication
ISSN: 2470-9905
Page 70
June 04-05, 2018
London, UK
3
rd
Edition of International Conference on
Advanced Spectroscopy,
Crystallography and Applications
in Modern Chemistry
D
iffraction in the polycrystal/crystalline powder is one of
the most powerful techniques in study of microstructure
and crystal structure of solids. This technique, in synergy with
microscopic, spectroscopic and other physical techniques,
enables a complete analysis of one- and multi-phase substances
thatareimportantinscientificandtechnologicalfields.Information
on microstructure and crystal structure of a substance is stored
in its diffraction pattern; in order to reveal this information, the
diffraction pattern should be decoded by application of adequate
mathematical and physical procedures which may often be
rather complex. During the last decades, diffraction techniques
in the polycrystal are developing rapidly due to the introduction
of sophisticated instrumentation, powerful computers and
by application of synchrotron radiation. This enables the
collection and interpretation of diffraction data in a short real
time, revealing: qualitative and quantitative phase analysis; 3D
distribution of electron density (e.g. in metallic glasses); accurate
measurement of periodicity in the crystalline substance; solubility
limits in solid solutions; precipitation processes in supersaturated
solid solutions (e.g. metallic alloys); thermal expansion; phase
transitions; phase diagrams; chemical stability, decomposition
of chemical compounds; crystallite size, kinetics of crystallite
growth, recrystallization, strains, annealing of defects; time-
resolved dynamical processes; crystal structure, 3D positions
of atoms, lengths and nature of chemical bonds, coordination,
conformation; resolution of lattice planes and rows of atoms in the
crystal; influence of crystal structure, microstructure and defects
on physical and chemical properties and on biological activity of a
substance, applications in a number of fields of human activities.
[1] Possibilities of diffraction techniques in the polycrystal are
illustrated by examples of authors’ studies: phase transitions in
TiO2, precipitation processes in Al-alloys, metastable and stable
phase diagramof Ga2Se3-In2Se3, the graphitization of petroleum
coke, biomineralization processes in bivalves, phase transitions
in thermosalient crystals.[2-5].
spopovic@phy.hrCONTEMPORARY DIFFRACTION METHODS IN STUDY OF POLYCRYSTALS
Stanko Popovic
1
, Antun Tonejc
2
and
Zeljko Skoko
3
1,2
Physics department, University of Zagreb, Croatia
3
Department of Experimental Physics, University of Zagreb, Croatia
Struct Chem Crystallogr Commun 2018, Volume 4
DOI: 10.21767/2470-9905-C1-006