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Elektronové vlastnosti sloučenin RPd5Al2
Zubáč, Jan ; Javorský, Pavel (advisor) ; Čermák, Petr (referee)
We have studied magnetic properties of the intermetallic NdPd5Al2 com- pound by means of specific heat and magnetization measurements and neutron scattering. The compound crystallizes in the tetragonal I4/mmm space group with lattice parameters a =4.147 ˚A and c =14.865 ˚A, orders antiferromagnet- ically below TN =1.3 K and presents large magnetocrystalline anisotropy due to the crystal-field effects. The obtained magnetic phase diagram is charac- terized by two distinct magnetically ordered phases similarly to structurally re- lated tetragonal RTX5 and R2TX8 compounds. The zero-field antiferromagnetic phase is characterized by the propagation vector k = (1 2 00) and antiferromag- netic coupling of Nd moments along the teragonal c-axis with the amplitude of magnetic moments of 2.22 µB/Nd as was revealed by neutron diffraction. The transition from the paramagnetic to magnetically ordered in zero field is the first-order phase transition. The CF excitations in NdPd5Al2 were detected by means of INS at 3.0 meV, 7.4 meV, 8.6 meV and 17.1 meV. We further compare our findings about CF in NdPd5Al2 obtained from INS, susceptibility analysis and first-principles calculations and confront them with the experimental mag- netization and magnetic specific heat data. Our results will be also discussed with respect to related...
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Determination of crystal field parameters in selected tetragonal compounds
Zubáč, Jan ; Javorský, Pavel (advisor) ; Prchal, Jiří (referee)
The thesis deals with a crystal electric field and its effect on magnetic properties of the in- termetalic tetragonal rare-earth compounds. Using the self-flux method we have prepared single crystals of two R2TIn8 type compounds, namely Nd2RhIn8 and Nd2IrIn8. These compounds or- der antiferromagnetically in low-temperature region. We have verified a proper structure through EDX analysis, X-ray powder diffraction and Laue diffraction method. Calculations of the crystal field parametres based on experimental magnetic susceptibilities data were performed. Apart from Nd2RhIn8, we have computed crystal field parameters for isostructural Nd2CoIn8 and Dy2CoIn8 compounds and cerium compound CeCuAl3. These compounds are studied simultaneously at our department.
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Elektronové vlastnosti sloučenin RPd5Al2
Zubáč, Jan ; Javorský, Pavel (advisor)
We have studied magnetic properties of the intermetallic NdPd5Al2 com- pound by means of specific heat and magnetization measurements and neutron scattering. The compound crystallizes in the tetragonal I4/mmm space group with lattice parameters a =4.147 ˚A and c =14.865 ˚A, orders antiferromagnet- ically below TN =1.3 K and presents large magnetocrystalline anisotropy due to the crystal-field effects. The obtained magnetic phase diagram is charac- terized by two distinct magnetically ordered phases similarly to structurally re- lated tetragonal RTX5 and R2TX8 compounds. The zero-field antiferromagnetic phase is characterized by the propagation vector k = (1 2 00) and antiferromag- netic coupling of Nd moments along the teragonal c-axis with the amplitude of magnetic moments of 2.22 µB/Nd as was revealed by neutron diffraction. The transition from the paramagnetic to magnetically ordered in zero field is the first-order phase transition. The CF excitations in NdPd5Al2 were detected by means of INS at 3.0 meV, 7.4 meV, 8.6 meV and 17.1 meV. We further compare our findings about CF in NdPd5Al2 obtained from INS, susceptibility analysis and first-principles calculations and confront them with the experimental mag- netization and magnetic specific heat data. Our results will be also discussed with respect to related...
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Elektronové vlastnosti sloučenin RPd5Al2
Zubáč, Jan ; Javorský, Pavel (advisor)
We have studied magnetic properties of the intermetallic NdPd5Al2 com- pound by means of specific heat and magnetization measurements and neutron scattering. The compound crystallizes in the tetragonal I4/mmm space group with lattice parameters a =4.147 ˚A and c =14.865 ˚A, orders antiferromagnet- ically below TN =1.3 K and presents large magnetocrystalline anisotropy due to the crystal-field effects. The obtained magnetic phase diagram is charac- terized by two distinct magnetically ordered phases similarly to structurally re- lated tetragonal RTX5 and R2TX8 compounds. The zero-field antiferromagnetic phase is characterized by the propagation vector k = (1 2 00) and antiferromag- netic coupling of Nd moments along the teragonal c-axis with the amplitude of magnetic moments of 2.22 µB/Nd as was revealed by neutron diffraction. The transition from the paramagnetic to magnetically ordered in zero field is the first-order phase transition. The CF excitations in NdPd5Al2 were detected by means of INS at 3.0 meV, 7.4 meV, 8.6 meV and 17.1 meV. We further compare our findings about CF in NdPd5Al2 obtained from INS, susceptibility analysis and first-principles calculations and confront them with the experimental mag- netization and magnetic specific heat data. Our results will be also discussed with respect to related...
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Elektronové vlastnosti sloučenin RPd5Al2
Zubáč, Jan ; Javorský, Pavel (advisor) ; Čermák, Petr (referee)
We have studied magnetic properties of the intermetallic NdPd5Al2 com- pound by means of specific heat and magnetization measurements and neutron scattering. The compound crystallizes in the tetragonal I4/mmm space group with lattice parameters a =4.147 ˚A and c =14.865 ˚A, orders antiferromagnet- ically below TN =1.3 K and presents large magnetocrystalline anisotropy due to the crystal-field effects. The obtained magnetic phase diagram is charac- terized by two distinct magnetically ordered phases similarly to structurally re- lated tetragonal RTX5 and R2TX8 compounds. The zero-field antiferromagnetic phase is characterized by the propagation vector k = (1 2 00) and antiferromag- netic coupling of Nd moments along the teragonal c-axis with the amplitude of magnetic moments of 2.22 µB/Nd as was revealed by neutron diffraction. The transition from the paramagnetic to magnetically ordered in zero field is the first-order phase transition. The CF excitations in NdPd5Al2 were detected by means of INS at 3.0 meV, 7.4 meV, 8.6 meV and 17.1 meV. We further compare our findings about CF in NdPd5Al2 obtained from INS, susceptibility analysis and first-principles calculations and confront them with the experimental mag- netization and magnetic specific heat data. Our results will be also discussed with respect to related...
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Determination of crystal field parameters in selected tetragonal compounds
Zubáč, Jan ; Javorský, Pavel (advisor) ; Prchal, Jiří (referee)
The thesis deals with a crystal electric field and its effect on magnetic properties of the in- termetalic tetragonal rare-earth compounds. Using the self-flux method we have prepared single crystals of two R2TIn8 type compounds, namely Nd2RhIn8 and Nd2IrIn8. These compounds or- der antiferromagnetically in low-temperature region. We have verified a proper structure through EDX analysis, X-ray powder diffraction and Laue diffraction method. Calculations of the crystal field parametres based on experimental magnetic susceptibilities data were performed. Apart from Nd2RhIn8, we have computed crystal field parameters for isostructural Nd2CoIn8 and Dy2CoIn8 compounds and cerium compound CeCuAl3. These compounds are studied simultaneously at our department.
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