Magnetic and elastic properties of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">Y</mml:mi><mml:msub><mml:mi mathvariant="normal">Co</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:mrow></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">La</mml:mi><mml:msub><mml:mi mathvariant="normal">Co</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:mrow></mml:math>under pressure

Koudela, Daniela; Schwarz, Ulrich; Rösner, H.; Burkhardt, Ulrich; Handstein, A.; Hanfland, Michael; Kuz’min, M. D.; Opahle, Ingo; Koepernik, Klaus; Müller, K.‐H.; Richter, Manuel

doi:10.1103/physrevb.77.024411

Cited by 26 publications

(40 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The magnetic anomaly develops parallelly with a sudden decrease of a c/a ratio, an isomorphous phase transition, respectively. Similar behaviour has been already evidenced in YCo5 compound and attributed [18] to a first order Lifshitz transition [19] or to a spin reorientation transition [20]. The transition develops, parallelly with the change of the Fermi surface topology.…”

Section: Resultssupporting

confidence: 79%

Exchange interactions and magnetic properties of hexagonal rare-earth-cobalt compounds

Burzo

2018

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

Abstract. The magnetic properties of some GdxY1-xCo4A compounds with A = Co, Si or B are analysed including the pressure effects. Isomorphous structure transitions, parallelly with changes of cobalt moments from high spin states to low spin states, were shown as pressure increases. The magnetic data, obtained from band structures, were compared with those predicted by the mean field model. IntroductionThe magnetic properties of RCo5-based compounds, where R is a rare earth or yttrium, were intensively investigated both from scientific reasons as well as in connection with their technical uses, as permanent magnets [1,2]. These compounds crystallize in a CaCu5-type structure, space group P6/mmm. In this lattice, the R atoms are located in 1a site and cobalt at 2c and 3g positions [1]. The RCo4B compounds have a hexagonal structure, derived from CaCu5 one, by replacing every two layers Co2c atoms by boron. There are two sites for R(1a, 1b) and Co(2c,6i) atoms and one for boron (2d) [3]. When R is a magnetic heavy rare-earth the above compounds are ferrimagnetically ordered, while for light rare earths, a parallel alignment of R and Co moments is shown. The easy axis of magnetization, for RCo5 compounds with R = Y or Gd, is the c-axis, as imposed by the local uniaxial anisotropy of the 2c sites, higher than the planar one favoured by 3g atoms [4], YCo4B shows also uniaxial anisotropy, at ambient temperature, which changes to planar one, at TsR = 159 K [5].The exchange interactions between magnetic rare-earths and cobalt are mediated by R5d band polarization, as suggested by the 4f-5d-3d model [6,7]. The above polarization is the result of both local 4f-5d exchange as well as due to R5d-Co3d short range interactions, hybridization effects, respectively. The exchange interactions between cobalt atoms are of short range as well as those between R5d-R5d orbitals, in addition to those by means of conduction electrons (RKKY-type) [8].In this paper, we analyse the exchange interactions in GdxY1-xCo4A series with A = Co, Si, B in the framework of mean field model [9], as well as based on the data obtained from their band structures. The pressure dependences of the cobalt moments, for end series compounds, are theoretically investigated. A linear dependence of cobalt moments on the exchange splitting energy of their 3d bands was shown.

show abstract

Section: Resultssupporting

confidence: 79%

Exchange interactions and magnetic properties of hexagonal rare-earth-cobalt compounds

Burzo

2018

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

show abstract

“…Materials with this hexagonal structure were especially investigated for possible extremely high magnetocrystalline anisotropy. In spite of their relatively old discovery the RCo 5 type compounds are still attracting much interest nowadays from both the experimental and theoretical point of view in order to deeper understand their intrinsic physical properties such as the magnetoelastic properties [5,6]; the exchange interactions [7,8]; the electronic structure [9,10] or the magnetocrystalline anisotropy [11,12]. * Corresponding author.…”

Section: Introductionmentioning

confidence: 99%

High magnetic field study of the anisotropy and neutron diffraction investigation of the crystal and magnetic structure of YCo4.5Ge0.5

Colin

Isnard

Guillot

2010

Journal of Alloys and Compounds

View full text Add to dashboard Cite

“…5(a). Recalling that an electronic topological (Lifshitz) transition of magnetoelastic origin was previously reported 55,56 in YCo 5 , one may expect a collapse of the magnetization or a crossover to a low-moment state to occur at rather low pressure in the Y 3 T 13 B 2 and Y 3 Ni 10 Co 3 B 2 compounds. However, the Y 3 Co 13 B 2 compound could be studied only in theory until it will be synthesized as a pure phase.…”

Section: Discussionmentioning

confidence: 99%

First principles calculations, neutron, and x-ray diffraction investigation of Y3Ni13B2, Y3Co13B2, and Y3Ni10Co3B2

Plugaru

Văleanu

Plugaru

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

Fully relativistic calculations within the local spin density approximation and the generalized gradient approximation were performed to determine the local spin and orbital magnetic moments, as well as the magnetocrystalline anisotropy energy of Y 3 Ni 13 B 2 , Y 3 Co 13 B 2 , and Y 3 Ni 10 Co 3 B 2 compounds. A weak in-plane magnetic anisotropy is determined for Y 3 Ni 13 B 2 , under the assumption of a crystallographic-like magnetic unit cell and collinear magnetic moments. The calculations predict considerable c-axis anisotropy for Y 3 Co 13 B 2 and Y 3 Ni 10 Co 3 B 2 , but smaller than that of YCo 5 . The values of the magnetocrystalline anisotropy energy correlate well with both the magnitude of the orbital magnetic moment and the orbital magnetic moment anisotropy. The mixing between Co or Ni 3d states and B 2p states, observable at the bottom of the valence band of the 3d metal having a boron atom nearest neighbor, decreases the 3d spin and especially, the 3d orbital magnetic moments. Y 3 Ni 13 B 2 and Y 3 Ni 10 Co 3 B 2 were also investigated by powder neutron diffraction experiments, at temperatures between 1.8 and 249 K. The Co and Ni site averaged magnetic moments calculated in the mixed compound are in fair agreement with the values obtained by the refinement of the magnetic contribution to the diffraction pattern. V C 2014 AIP Publishing LLC.

show abstract

Magnetic and elastic properties ofYCo5andLaCo5under pressure

Cited by 26 publications

References 15 publications

Exchange interactions and magnetic properties of hexagonal rare-earth-cobalt compounds

Exchange interactions and magnetic properties of hexagonal rare-earth-cobalt compounds

High magnetic field study of the anisotropy and neutron diffraction investigation of the crystal and magnetic structure of YCo4.5Ge0.5

First principles calculations, neutron, and x-ray diffraction investigation of Y3Ni13B2, Y3Co13B2, and Y3Ni10Co3B2

Contact Info

Product

Resources

About