INTECIN   20395
INSTITUTO DE TECNOLOGIAS Y CIENCIAS DE LA INGENIERIA "HILARIO FERNANDEZ LONG"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Ab-initio study of Fe-doped SnO2
Autor/es:
A.M. MUDARRA NAVARRO, L.ERRICO, V. BILOVOL, A.F. CABRERA AND C.E. RODRÍGUEZ TORRES
Lugar:
Lima, Perú
Reunión:
Conferencia; XII Latin American Conference on the Applications of the Mossbauer Effect; 2010
Resumen:
In this work we report hyperfine parameters at the Fe
site and the equilibrium interatomic distances calculated
by ab-initio methods
for different impurity-oxygen vacancies configurations and for two Fe
concentrations. The predictions are compared with experimental results obtained
by Mössbauer and X-ray absorption spectroscopies for
powder samples prepared by mechanosynthesis and sol-gel methods.
The comparison between experimental and theoretical
results for the hyperfine parameters (isomer shift and quadrupole splittings) and
Fe-O bond-lengths allow us to conclude that the oxygen vacancies are located in
the first coordination sphere of Fe atoms in all studied samples.
Additionally, we study the magnetic alignment between Fe
atoms considering different distributions of impurities in the SnO2 host. Our results
show that the coupling is antiferromagnetic when the Fe atoms
share oxygen atoms, but the system becomes ferromagnetic when vacancies are
located between irons.