Navegação Ciências Exatas e da Terra por Assunto "Difração de nêutrons"
Resultados 1-6 de 6
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Large resistivity change and phase transition in the antiferromagnetic semiconductors LiMnAs and LaOMnAs
(2013) [Artigo de periódico]Antiferromagnetic semiconductors are new alternative materials for spintronic applications and spin valves. In this work, we report a detailed investigation of two antiferromagnetic semiconductors AMnAs (A = Li, LaO), which ... -
Magnetic behavior of the NixFe1−xNb2O6 quasi-one-dimensional system : isolation of Ising chains by frustration
(2012) [Artigo de periódico]Physical properties of the NixFe1−xNb2O6 compounds are investigated combining x-ray and neutron powder diffraction with magnetic and calorimetry measurements as well as 57Fe Mössbauer spectroscopy. This system is known to ... -
Mesoscopic magnetic states in metallic alloys with strong electronic correlations : a percolative scenario for CeNi/sub 1-x/Cu/sub x/
(2007) [Artigo de periódico]We present evidence for the existence of magnetic clusters of approximately 20 Å in the strongly correlated alloy system CeNi1-xCux (0.7 ≤ x ≤ 0.2) based on small angle neutron scattering experiments as well as the occurrence ... -
A new approach for the determination of multiple cation locations and ordering, using the example of natural and heat-treated columbites
(2011) [Artigo de periódico]A new approach is proposed to determine unambiguously the location of four cations within the crystal structure of a natural AB2O6 columbite-type compound and derivatives, when submitted to order–disorder transitions caused ... -
Structural and spectroscopic investigation of the charge-ordered, short-range ordered, and disordered phases of the Co3O2BO3 ludwigite
(2021) [Artigo de periódico]Charge ordering is prone to occur in crystalline materials with mixed-valence ions. It is presumably accompanied by a structural phase transition, with possible exceptions in compounds that already present more than one ... -
Suppression of magnetic ordering in quasi-one-dimensional FexCo1−xNb2O6 compounds
(2011) [Artigo de periódico]We present a systematic investigation of the series of compounds FexCo1−xNb2O6 by means of x-ray and neutron powder diffraction combined with magnetic measurements, carried out in the paramagnetic as well as in the ordered ...