Abstract
Polycrystalline samples of Fe3-yGeTe2 (0.08 <= y <= 0.29) and the solid solutions Fe3-x-yNixGeTe2 (0.24 <= x <= 1.32;0.14 <= y <= 0.41) were synthesized at 898-973 K in a resistance furnace and characterized by X-ray and neutron powder diffraction with Rietveld analysis (Fe3GeTe2 type, P6(3)/mmc, a = 402.665(3), c = 1632.820(14) pm for x = 0, y = 0.08). Fe 3 Ge layers with planar FeGe hexagons and additional iron atoms above and below the rings are separated by double layers of tellurium atoms. Fe3GeTe2 is ferromagnetic below T-C = 230 K with magnetic moments aligned along the c axis. T-C depends on the iron content and decreases with increasing iron vacancies continuously to 153 K in Fe2.71GeTe2. Further reduction of T-C is possible by nickel substitution until magnetic ordering is nearly absent in Fe1.33Ni1.32GeTe2. The suppression of the magnetic ordering is caused by random dilution of the magnetic iron atoms either by vacancies or by non-magnetic nickel atoms.
Item Type: | Journal article |
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Faculties: | Chemistry and Pharmacy > Department of Chemistry |
Subjects: | 500 Science > 540 Chemistry |
ISSN: | 0932-0776 |
Language: | English |
Item ID: | 48255 |
Date Deposited: | 27. Apr 2018, 08:15 |
Last Modified: | 04. Nov 2020, 13:25 |