scholarly journals Noncollinear Fe spin structure in (Sm-Co)/Fe exchange-spring bilayers: Layer-resolved57Fe Mössbauer spectroscopy and electronic structure calculations

2012 ◽  
Vol 85 (2) ◽  
Author(s):  
V. M. Uzdin ◽  
A. Vega ◽  
A. Khrenov ◽  
W. Keune ◽  
V. E. Kuncser ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Mössbauer Spectroscopy ◽  
Spin Structure ◽  
Mossbauer Spectroscopy ◽  
Electronic Structure Calculations ◽  
Mößbauer Spectroscopy ◽  
Exchange Spring ◽  
Structure Calculations

scholarly journals Structure and Magnetic Properties of Bulk Synthesized Mn2−xFexP1−ySiy Compounds from Magnetization, 57Fe Mössbauer Spectroscopy, and Electronic Structure Calculations

Crystals ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 37 ◽  
Author(s):  
Daniel Fruchart ◽  
Sonia Haj-Khlifa ◽  
Patricia de Rango ◽  
Mohamed Balli ◽  
Ryszard Zach ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Mössbauer Spectroscopy ◽  
Large Scale ◽  
Mossbauer Spectroscopy ◽  
Magnetic Transition ◽  
Electronic Structure Calculations ◽  
Synthesis Process ◽  
Hyperfine Fields ◽  
Mößbauer Spectroscopy ◽  
Structure Calculations

The series of Mn2−xFexP1−ySiy types of compounds form one of the most promising families of magnetocaloric materials in term of performances and availability of the elemental components. Potential for large scale application needs to optimize the synthesis process, and an easy and rather fast process here described is based on the use of two main type of precursors, providing the Fe-P and Mn-Si proportions. The series of Mn2−xFexP1−ySiy compounds were synthesized and carefully investigated for their crystal structure versus temperature and compared interestingly with earlier results. A strong magnetoelastic effect accompanying the 1st order magnetic transition—as well as the parent phosphide–arsenides—was related to the relative stability of both the Fe magnetic polarization and the Fe–Fe exchange couplings. In order to better understand this effect, we propose a local distortion index of the non-metal tetrahedron hosting Fe atoms. Besides, from Mn-rich (Si-rich) to Fe-rich (P-rich) compositions, it is shown that the magnetocaloric phenomenon can be established on demand below and above room temperature. Excellent performance compounds were realized in terms of magnetic entropy ΔSm and adiabatic temperature ΔTad variations. Since from literature it was seen that the magnetic performances are very sensitive to the synthesis process, correspondingly here a new effective process is proposed. Mössbauer spectroscopy analysis was performed on Mn-rich, equi-atomic Mn-Fe, and Fe-rich compounds, allowing determination of the distribution of hyperfine fields setting on Fe in the tetrahedral and pyramidal sites, respectively. Electronic structure calculations confirmed the scheme of metal and non-metal preferential ordering, respectively. Moreover, the local magnetic moments were derived, in fair agreement with both the experimental magnetization and the Fe contributions, as determined by Mössbauer spectroscopy.

Helical spin structure in the langasite family multiferroic Ba3TaFe3Si2O14, determined by Mössbauer spectroscopy

2020 ◽  
Vol 128 (6) ◽  
pp. 67005
Author(s):  
I. S. Lyubutin ◽  
M. A. Chuev ◽  
S. S. Starchikov ◽  
K. O. Funtov ◽  
I. Yu. Starchikova
Keyword(s):  
Mössbauer Spectroscopy ◽  
Spin Structure ◽  
Mossbauer Spectroscopy ◽  
Mößbauer Spectroscopy

Nanostructural Studies by MÖssbauer Spectroscopy

1994 ◽  
Vol 332 ◽  
Author(s):  
Georgia C. Papaefthymiou
Keyword(s):  
Mössbauer Spectroscopy ◽  
Spin Structure ◽  
Mossbauer Spectroscopy ◽  
Variable Temperature ◽  
Structural Parameters ◽  
Nanoscale Systems ◽  
Mößbauer Spectroscopy ◽  
Dynamical Spin ◽  
Microscopic Picture

ABSTRACTApplication of 57Fe MÖssbauer spectroscopy to the determination of magnetic structural parameters relevant to nanostructural studies is discussed. Variable temperature and applied magnetic field strength investigations are considered in order to illustrate the power of the technique in rendering a microscopic picture of the internal spin structure and dynamical spin relaxation phenomena associated with nanoscale systems. Examples from biology and chemistry, where iron aggregates of nanometer dimensions are encountered, are presented.

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