SIGs
Role and constitution of a SIG
|
|
Promotors:
Giovanni Ferraris, Torino,
Italy
Dmitry Pushcharovsky, Moscow,
Russia
Proponents:
five ECA councillours
Leonid A. Aslanov, Moscow,
Russia
Giovanni Ferraris, Torino, Italy
Alajos Kalman, Budapest, Hungary
Boris Kamenar, Zagreb, Croatia
Jan Kroon, Utrecht, The Netherlands
Introduction:
A Special Interest Group (SIG) on Mineralogical
Crystallography (renamed Mineral and Inorganic Crystallography in August 2008) is proposed under the auspices of the
European Crystallographic Association (ECA).
Modern Mineralogy is focussed on the fine-scale
characterization of the structure and properties of
minerals and related compounds, thus being
essentially a Geo-material Science.
Although the number of newly characterised mineral
species is low when compared to that of small molecules,
the capability of their characterization is rapidly
improving, and presently allows the understanding of very
fine-scale details with are crucial to model
physical and chemical properties. In particular,
crystallographic methods are a fundamental tool for
mineral characterization, and can provide
constraints for interpreting the results of other
techniques and a basis for a reliable modelling of
mineral behaviour.
These models are particularly important as they provide
extrapolation to intensive conditions (P, T, fO2,
XH2O, bulk composition) which cannot be
experimentally verified by characterization of natural
material and/or the products of syntheses under
controlled conditions. Rock samples coming from the deep
interior of the Earth are sporadically available,
and cannot represent the possible geological
situations. For instance, a sample blasted out from 250
km in a kimberlite pipe in Lesoto (South Africa)
represents the deepest available rock, whereas the
deepest drilling in Kola Peninsula (Russia) could
achieve "only" the level of 12.2 km. Uplifting
geological processes (and erosion) brought to surface few
metamorphic rocks from (perhaps) 100 km; however, they
most probably re-equilibrated during uplift. Within
the last few decades extraterrestrial (lunar,
martian and interstellar) material became also available,
and will be increasingly accessible for mineralogical
studies.
In this respect, mineralogists are particularly
interested in the development of high-pressure/high-temperature
(crystallographic) techniques, which allow
simulation of the matter in the interior of the
Earth and in extraterrestial conditions. The development
and availability of intense- and micro-beam radiation
sources (synchrotron radiation) also is opening a
new era for characterizing micrometric
samples and for the physics and chemistry of minerals, in
that it allows in situ determination of (very rapid)
cation-ordering processes and phase transitions even on
very small crystals or on powdered material. The
combination of structural data with the new information
from spectroscopies based on synchrotron radiation and (pulsed)
neutron sources is also giving extremely promising
results. To sum up, the experimental and theoretical
problems to be faced by mineralogists, physicists and
chemists of minerals span from synthesis and
crystal growth to the characterization of the structure
and properties, through modelling and development
of new methods. For the study of minerals, all
crystallographic methods are fundamental tools,
from diffraction (X-rays, neutrons, electrons) to
microscopy and spectroscopy, from mathematical to
physical and crystal-chemical aspects of the
crystalline solid state. In particular, powerful methods
for the solution of very complex structures from
poorly crystalline materials, and for the improvement
of the accuracy and the precision of the refinement's
results would be important. That follows from the
fact that most of the challenging aspects of modern
crystallography are present in minerals, such as:
a) Complicate crystal-chemistry due to the presence of
isomorphous substitutions and the
absence of discrete units (molecules);
minerals are actually infinite arrays of atoms.
b) Atomic order/disorder at the long- and short-range
level which reflect the conditions
experienced by the host rock and may
be used to accurately model thermodynamics and
kinetics of the geological processes.
c) Real structures with defects and modulation, resulting,
together with b), from deviations from
thermodynamic equilibrium.
d) Structural modularity (polytypism, polysomatism).
e) Phase transitions.
f) Low crystallinity and disordered materials.
Programme
The proposed SIG shall focus in particular on:
1. Development and application of theoretical and
experimental aspects of the crystal-
chemistry of minerals and related
inorganic structures (including solving, modelling
and predicting crystal structures and
their properties).
2. Development and application of theoretical and
experimental methods (particularly in the
fields of diffraction, spectroscopy,
microscopy, crystal growth and symmetry) for
characterising average and real
aspects of this type of structures, also as a function of
thermodynamically relevant parameters
such as temperature, hydrostatic and non-hydrostatic
pressure, electric and magnetic
fields, oxygen and sulphur fugacities, and water activity.
3. Formulation and definition of the terms and
language specific of the field, including the
systematic of minerals and related
materials.
4. Preparation and availability of databases and computer programs.
5. Exchange of scientific and teaching information.
6. Organisation of local and international workshops,
lecture courses, symposia, etc., with
particular reference to the ECM
meetings.
7. The topics to be covered by the SIG on
Mineralogical Crystallography shall include
everything dealing with experimental
charge densities and related theoretical calculations as
far as related to or applicable
to Mineralogical Crystallography.
RULES
The following list of members of the SIG of
Mineralogical Crystallography is far from including all
the European mineralogists involved with crystallography.
The aim of the promoters has been to obtain the
assent of a representative group of scientists who, in
different European countries, can serve as a first
reference for the activities of the European
Crystallographic Association in the field of mineralogy
and inorganic structures. After approval of the SIG, the
membership of the SIG is intended open to all European
crystallographers active in the field of mineralogy. It
is intention of the promoters to have a meeting of the
Founding members and other interested crystallographers
either in Glasgow during IUCr-18 or (latest time) in
Nancy during the next ECM. In this meeting more formal
rules should be established and officers of the SIG (chairman,
vice-chairman, secretary) should be formally elected.
Till that time, the promoters shall act as contact
persons with ECA (G. Ferraris, chairman; D. Pushcharovsky,
vice-chairman).
FOUNDING MEMBERS
Giovanni Ferraris, Torino,
Italy
Dmitry Pushcharovsky, Moscow, Russia
Thomas Armbruster, Bern, Switzerland
Leonid A. Aslanov, Moscow, Russia
Maria Franca Brigatti, Modena, Italy
Georges Calas, Paris, France
Michael Czank, Kiel, Germany
Martin Dove, Cambridge, U.K.
Slavomil Durovic, Bratislava, Slovak Rep.
Matthias Gottschalk, Potsdam, Germany
Bernard Grobety, Fribourg, Switzerland
Jiri Hybler, Praha, Czech Republic
Paul Keller, Stuttgart, Germany
Natasha Khisina, Moscow, Russia
Martin Kunz, ETH Zuerich, Switzerland
Gyuri Ilinca, Bucharest, Romania
Ole Johnsen, Copenhagen, Denmark
Claude Lecomte, Nancy, France
Friedrich Liebau, Kiel, Germany
Marcello Mellini, Siena, Italy
Stefano Merlino, Pisa, Italy
Roberta Oberti, Pavia, Italy
Artem R. Oganov, London, U.K.
Peter Paufler, Dresden, Germany
Andrew Putnis, Muenster, Germany
Surendra K. Saxena, Uppsala, Sweden
Roman Skala, Praha, Czech Rep.
Elena V. Sokolova, Moscow, Russia
Ekkehart Tillmanns, Wien, Austria
Vadim S. Urusov, Moscow, Russia
Zdenek Weiss, Ostrava-Poruba, Czech Rep.
Pier Francesco Zanazzi, Perugia, Italia
For more information see the Mineral and Inorganic Crystallography SIG Home Page
