XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
33
I–15
Advanced theoretical modelling of selected model nanosystems
Zdzisław Latajka
1
, Andrzej Bil
1
, and Piotr Okrasiński
1
1
Faculty of Chemistry,University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland,
e-mail: zdzislaw.latajka@chem.uni.wroc.pl
Nowadays the advanced quantum chemical methods are very widely applied in study and
design of new materials. First-principle methods enable one to study the electronic and
geometrical structure of molecular systems as accurately as possible with modern computational
effort. Moreover, using ab initio molecular dynamics methods, which calculate the forces
exerted on atoms at each time step of simulation, one can calculate the evolution of atomic and
electronic motions without assuming empirical parameters.
Very important and the most famous nanometer scale materials are fullerene. Although the
number of papers devoted to fullerenes is large and growing rapidly, only a small proportion
concerns fullerene oxides. Unlike the C
60
molecule, C
70
has five non-equivalent carbon atom
types, which leads to eight non-equivalent C–C bonds. There are therefore at least eight a
priori
possible isomers of C
70
O. A series of ab initio calculations have been carried out to
determine the stability of different isomers of mono-oxides and mono-ozonides of C
70
. On the
basis of density functional theory method calculations and Born-Oppenheimer molecular
dynamics will be presented a mechanism for the thermally induced dissociation of C
70
O
3
. It is
interesting to note that the first to steps of studied process is identical with the general
mechanism for ozonolysis of alkenes proposed by Criegee. Moreover, the results of molecular
dynamics simulations of C
70
O
3
doped with light molecules will be also discussed.
Carbon nanotubes (CNTs) play an important role in materials chemistry and are the subject
of many experimental as well as theoretical studies. Open-ended single-walled carbon nanotubes
(SWCNTs) are considered in many studies as a model system in nanoconfined chemistry. In the
lecture will be presented analysis the noncovalent interaction between the cyclic formic acid
dimer (FAD) and pyrene, which was used as a simple model for a CNT wall. Moreover, will be
presented results for FAD in an armchair (6,6) SWCNT as an example for a smaller nanotube
and in an armchair (8,8) SWCNT as an example for a larger one.
Keywords: carbon nanotubes; fullerenes; molecular modelling
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
34
I–16
Implementation of GIXRD analysis and nanoindenation technique
to study functional properties of materials – ODS case study
Lukasz Kurpaska
1
, Malgorzata Frelek-Kozak
1
, Wioleta Pawlak
1
,
Magdalena Leśniak
2
, Iwona Jozwik
3
, Jaroslaw Jasinki4,
Marcin Chmielewski
3
, and Jacek Jagielski
1,3
1
Material Physics Department, National Centre for Nuclear Research, st. Andrzeja Soltana 7, 05-400
Otwock-Swierk, Poland, e-mail: lukasz.kurpaska@ncbj.gov.pl
2
Faculty of Energy and Fuels, AGH University of Science and Technology, av. A. Mickiewicza 30,
30-059 Krakow, Poland
3
Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw, Poland
4
Institute of Materials Science, Czestochowa University of Science and Technology, av. Armii
Krajowej 19, 42-200, Czestochowa, Poland
Due to its promising properties, Ferritic Oxide Dispersion Strengthened (ODS) steels are one
of the best candidate materials for future nuclear applications, such as structural components of
IV-gen reactors [1]. Uniqueness of ODS is an effect of the presence of certain elements (Y-Ti-
O or Y-Al-O nanoparticles), high dislocation density and fine-grain microstructure [1–2]. Since,
these steels are previsioned to be used in construction elements of GenIV nuclear reactors, they
will be exposed to severe irradiation damage. It has been proven that irradiation damage changes
structural and mechanical properties of the materials [3]. The fundamental phenomenon
responsible for this effect is the generation of radiation damage which leads to several structural
modifications, mainly development of defects. For example, it is known that increase of
irradiation dose can result in the agglomeration of vacancies and interstitials into voids and
dislocation loops and lead to swelling [4]. The most efficient way of modelling processes
occurring in materials during long term exposure to radiation is the use of accelerated ion
beams. Such an approach allows one to obtain high damage levels (~100 dpa) in one day instead
of several years in research reactors. Moreover, the irradiated samples do not become
radioactive, making their analysis much simpler and safer. However, the main disadvantage of
the use of ion beams is the fact, that damaged layer is usually less than one micrometer thick.
Consequently the structural and mechanical properties of thin film may be studied by only very
precise techniques.
In this work, the effect of ion implantation on mechanical and structural properties of ODS
steel have been investigated. Structural properties were measured by using Grazing Incidence X-
ray Diffraction (GIXRD) and Small Angle Neutron Scattering (SANS) methods. Mechanical
properties were measured by nanoindentation technique. Correlation between obtained
mechanical and structural results have been shown. Recorded results show that ion-irradiation
causes hardening effect which may be associated with creation of radiation defect and
dislocation loops.
Keywords: X-ray, ODS, ion implantation
Acknowledgment
Financial support from Ministry of Science and Higher Education through “Young Scientist” programme is
gratefully acknowledged.
References
[1] C. Heintze, M. Hernandez-Mayoral, A. Ulbricht, F. Bergner, A. Shariq, T. Weissgärber, H.
Frielinghaus, J Nucl. Mater. 428 (2012) 139.
[2] C.L. Chen, A. Richter, R. Kögler, M. Griepentrog, P. Reinstädt, J. Alloys Compd. 615 (2014) S448.
[3] C.L. Chen, A. Richter, R. Kogler, G. Talut, J Nucl. Mater. 412 (2011) 350.
[4] C.L. Chen, A. Richter, R. Kogler, L.T. Wu, J. Alloys Compd. 536S (2012) S194.
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