Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3
Polycrystalline samples of FeMo4Ge3 have been synthesized by the reduction of an oxide mixture at 1248 K and characterized by a combination of diffraction, muon spin relaxation (μ+SR), Mössbauer spectroscopy, magnetometry, transport, and heat-capacity measurements. The compound adopts a tetragonal W...
| Main Authors: | , , , , , , , |
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| Format: | Journal article |
| Language: | English |
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American Physical Society
2008
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| Subjects: |
| _version_ | 1797071573027389440 |
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| author | Baker, P Battle, P Blundell, S Grandjean, F Lancaster, T Long, G Oldham, S Prior, T |
| author_facet | Baker, P Battle, P Blundell, S Grandjean, F Lancaster, T Long, G Oldham, S Prior, T |
| author_sort | Baker, P |
| collection | OXFORD |
| description | Polycrystalline samples of FeMo4Ge3 have been synthesized by the reduction of an oxide mixture at 1248 K and characterized by a combination of diffraction, muon spin relaxation (μ+SR), Mössbauer spectroscopy, magnetometry, transport, and heat-capacity measurements. The compound adopts a tetragonal W5Si3 structure (space group I4/mcm); the iron and molybdenum atoms are disordered over two crystallographic sites, 16k and either 4a or 4b. The synthesis conditions determine which fourfold site is selected; occupation of either leads to the presence of one-dimensional chains of transition metals in the structure. In both cases, the electrical resistivity below 200 K is ~ 175μΩ cm. The dc magnetization rapidly rises below 35 K (Fe/Mo on 16k and 4b sites) or 16 K (16k and 4a sites), and a magnetization of 1μB or 0.8��B per Fe atom is observed in 4 T at 2 K. The ac susceptibility and the heat capacity both suggest that these are glasslike magnetic transitions, although the transition shows a more complex temperature dependence (with two maxima in X'') when the 4b sites are partially occupied by iron. No long-range magnetic order is thought to be present at 5 K in either structural form; this has been proven by neutron diffraction and μ+SR for the case when Fe and Mo occupy the 16k and 4b sites. |
| first_indexed | 2024-03-06T22:55:15Z |
| format | Journal article |
| id | oxford-uuid:6025e8e9-462b-4de7-a57b-ce89ad16bbe2 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T22:55:15Z |
| publishDate | 2008 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | oxford-uuid:6025e8e9-462b-4de7-a57b-ce89ad16bbe22022-03-26T17:51:35ZSynthesis and characterization of two metallic spin-glass phases of FeMo4Ge3Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:6025e8e9-462b-4de7-a57b-ce89ad16bbe2PhysicsEnglishOxford University Research Archive - ValetAmerican Physical Society2008Baker, PBattle, PBlundell, SGrandjean, FLancaster, TLong, GOldham, SPrior, TPolycrystalline samples of FeMo4Ge3 have been synthesized by the reduction of an oxide mixture at 1248 K and characterized by a combination of diffraction, muon spin relaxation (μ+SR), Mössbauer spectroscopy, magnetometry, transport, and heat-capacity measurements. The compound adopts a tetragonal W5Si3 structure (space group I4/mcm); the iron and molybdenum atoms are disordered over two crystallographic sites, 16k and either 4a or 4b. The synthesis conditions determine which fourfold site is selected; occupation of either leads to the presence of one-dimensional chains of transition metals in the structure. In both cases, the electrical resistivity below 200 K is ~ 175μΩ cm. The dc magnetization rapidly rises below 35 K (Fe/Mo on 16k and 4b sites) or 16 K (16k and 4a sites), and a magnetization of 1μB or 0.8��B per Fe atom is observed in 4 T at 2 K. The ac susceptibility and the heat capacity both suggest that these are glasslike magnetic transitions, although the transition shows a more complex temperature dependence (with two maxima in X'') when the 4b sites are partially occupied by iron. No long-range magnetic order is thought to be present at 5 K in either structural form; this has been proven by neutron diffraction and μ+SR for the case when Fe and Mo occupy the 16k and 4b sites. |
| spellingShingle | Physics Baker, P Battle, P Blundell, S Grandjean, F Lancaster, T Long, G Oldham, S Prior, T Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3 |
| title | Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3 |
| title_full | Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3 |
| title_fullStr | Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3 |
| title_full_unstemmed | Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3 |
| title_short | Synthesis and characterization of two metallic spin-glass phases of FeMo4Ge3 |
| title_sort | synthesis and characterization of two metallic spin glass phases of femo4ge3 |
| topic | Physics |
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