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Table 1. Properties of Ln;_,A,MnO3

Table 1 Properties of Ln;_,A,MnO3

Related Figures (22)

Figure 2. Magnetization and ac magnetic susceptibility of Laj-,A,MnO3 compositions (after ref 15). Figure 1. Magnetic structure of antiferromagnetic LaMnOs, antiferromagnetic CaMnOs, and ferromagnetic Lao,7A93MnOs. Two possible FM orderings of Mn ions are shown for the latter (after ref 14).
Figure 2. Magnetization and ac magnetic susceptibility of Laj-,A,MnO3 compositions (after ref 15). Figure 1. Magnetic structure of antiferromagnetic LaMnOs, antiferromagnetic CaMnOs, and ferromagnetic Lao,7A93MnOs. Two possible FM orderings of Mn ions are shown for the latter (after ref 14).
Figure 3. Approximate temperature—composition diagram of La,;_,A,MnO3: CSI, canted-spin insulator; FMI, ferromag- netic insulator; FMM, ferromagnetic metal; AFMI, antiferro- magnetic insulator; PMI, paramagnetic insulator; PMM, para- magnetic metal (adapted from ref 16). @ Obtained by redox titrations. ® PC, polycrystal; SC, single crystal; TF, thin film. “ Magnetic field strength is shown in parentheses.
Figure 3. Approximate temperature—composition diagram of La,;_,A,MnO3: CSI, canted-spin insulator; FMI, ferromag- netic insulator; FMM, ferromagnetic metal; AFMI, antiferro- magnetic insulator; PMI, paramagnetic insulator; PMM, para- magnetic metal (adapted from ref 16). @ Obtained by redox titrations. ® PC, polycrystal; SC, single crystal; TF, thin film. “ Magnetic field strength is shown in parentheses.
Figure 4. Temperature variation of magnetization, resistivity and magnetoresistance of Lao.75Cao2sMnO3 in various fields (from ref 16).
Figure 4. Temperature variation of magnetization, resistivity and magnetoresistance of Lao.75Cao2sMnO3 in various fields (from ref 16).
Figure 5. Temperature variation of the magnetoresistance of polycrystalline La,_,Ca,MnOs3.
Figure 5. Temperature variation of the magnetoresistance of polycrystalline La,_,Ca,MnOs3.
Figure 6. Variation of magnetoresistance of polycrystalline Laj-_,Sr,MnO3 with magnetic field, H (from ref 15).
Figure 6. Variation of magnetoresistance of polycrystalline Laj-_,Sr,MnO3 with magnetic field, H (from ref 15).
Figure 7. (a) Magnetization data of polycrystalline Lao 945- Mno 94503; (b) resistivity—temperature plots for polycrystalline Lao.945Mno 94503 at different magnetic fields (after ref 15).
Figure 7. (a) Magnetization data of polycrystalline Lao 945- Mno 94503; (b) resistivity—temperature plots for polycrystalline Lao.945Mno 94503 at different magnetic fields (after ref 15).
Figure 8. Magnetoresistance of a thin film of La;_,Ca,MnO3 (after ref 32f).
Figure 8. Magnetoresistance of a thin film of La;_,Ca,MnO3 (after ref 32f).
Figure 11. Resistivity—temperature plots of Lao ss5Sro.1sMnO3 at different magnetic fields (after ref 9). Figure 10. Phase diagram of La,_,Sr,MnOs (after ref 9).
Figure 11. Resistivity—temperature plots of Lao ss5Sro.1sMnO3 at different magnetic fields (after ref 9). Figure 10. Phase diagram of La,_,Sr,MnOs (after ref 9).
Figure 9. Temperature variation of the resistivity of a single crystal of La,_,Sr,MnOs3 (after ref 9).
Figure 9. Temperature variation of the resistivity of a single crystal of La,_,Sr,MnOs3 (after ref 9).
Figure 12. Variation of T. (Tim) of Lno7zAo3MnO3 with hydrostatic pressure and the weighted average radius of the A-site cations (from ref 47).
Figure 12. Variation of T. (Tim) of Lno7zAo3MnO3 with hydrostatic pressure and the weighted average radius of the A-site cations (from ref 47).
Figure 14. Variation of the magnetoresistance of Ln;-,A,MnO3 with the weighted average radius of the A site cations, ra ; the inset shows the variation of log pp with ra (after ref 27).
Figure 14. Variation of the magnetoresistance of Ln;-,A,MnO3 with the weighted average radius of the A site cations, ra ; the inset shows the variation of log pp with ra (after ref 27).
Figure 15. Photoelectron spectra of Lai—,.Sr,MnOz3 in the valence region at room temperature (from ref 60a).
Figure 15. Photoelectron spectra of Lai—,.Sr,MnOz3 in the valence region at room temperature (from ref 60a).
Figure 16. Temperature variation of (a) magnetization, (b) lattice parameters, and (c) resistivity of NdosSrosMnOs3 single crystal (from ref 68).
Figure 16. Temperature variation of (a) magnetization, (b) lattice parameters, and (c) resistivity of NdosSrosMnOs3 single crystal (from ref 68).
Figure 17. Temperature variation of resistivity under H = 0, 6, and 12 T in Pri_,Ca,MnO3 (x = 0.35) crystal (from ref 70).
Figure 17. Temperature variation of resistivity under H = 0, 6, and 12 T in Pri_,Ca,MnO3 (x = 0.35) crystal (from ref 70).
also therefore different as suggested by Yoshizawa.?° The competition between the ferromagnetic double- exchange interaction and the antiferromagnetic charge- ordering instability has been examined in (Nd,Sm)o5Sro0.5- MnO3.72, In Pro.7Cao3MnOs3, an insulating charge- ordered state (To. ~ 200 K) becomes antiferromagnetic around 140 K (Ty) and then undergoes a transformation to a canted-spin antiferromagnetic state at a still lower Figure 18. Changes in the resistivity of Ndo.sSrosMnOs3 with increasing and decreasing magnetic fields. Notice the sharp jump in resistivity at the lower and upper critical fields (from ref 68). Charge ordering in the manganates is governed by the width of the e, band which is directly determined by the weighted average radius of the A-site cations, ra, or the tolerance factor, t. This is because a distortion of the Mn—O—Mn bond angle affects the transfer interaction of the eg conduction electrons (holes). We can describe the spin and charge-ordering phenomena in the rare-earth manganate systems in erms of the generalized phase diagram shown in Figure 20. The diagram shows that when ry, is large (e.g., Liay—,Sr,MnOs), only ferromagnetism and the associated —M transition are found with no charge ordering. With decreasing ra , the ferromagnetic charge—liquid state transforms to the antiferromagnetic charge ordered
also therefore different as suggested by Yoshizawa.?° The competition between the ferromagnetic double- exchange interaction and the antiferromagnetic charge- ordering instability has been examined in (Nd,Sm)o5Sro0.5- MnO3.72, In Pro.7Cao3MnOs3, an insulating charge- ordered state (To. ~ 200 K) becomes antiferromagnetic around 140 K (Ty) and then undergoes a transformation to a canted-spin antiferromagnetic state at a still lower Figure 18. Changes in the resistivity of Ndo.sSrosMnOs3 with increasing and decreasing magnetic fields. Notice the sharp jump in resistivity at the lower and upper critical fields (from ref 68). Charge ordering in the manganates is governed by the width of the e, band which is directly determined by the weighted average radius of the A-site cations, ra, or the tolerance factor, t. This is because a distortion of the Mn—O—Mn bond angle affects the transfer interaction of the eg conduction electrons (holes). We can describe the spin and charge-ordering phenomena in the rare-earth manganate systems in erms of the generalized phase diagram shown in Figure 20. The diagram shows that when ry, is large (e.g., Liay—,Sr,MnOs), only ferromagnetism and the associated —M transition are found with no charge ordering. With decreasing ra , the ferromagnetic charge—liquid state transforms to the antiferromagnetic charge ordered
Figure 19. Electronic phase diagrams in the T—H plane of (a) Pri-,Sr,MnOs (« = 0.5), (b) Ndi-.Srr:MnO3 (x = 0.5), and (c) Pri-,Ca,MnOs3 (x = 0.35) (from ref 67).
Figure 19. Electronic phase diagrams in the T—H plane of (a) Pri-,Sr,MnOs (« = 0.5), (b) Ndi-.Srr:MnO3 (x = 0.5), and (c) Pri-,Ca,MnOs3 (x = 0.35) (from ref 67).
Figure 21. Magnetic and electronic phase diagrams of (a) Pri_,Sr,MnO3 and (b) Pri-,Ca,MnO;: PMI, paramagnetic insulator; PMM, paramagnetic metal; CSI, canted spin insula- tor; FMI, ferromagnetic insulator; FMM, ferromagnetic metal; AFMI, antiferromagnetic insulator; CAFMI, canted antifer- romagnetic insulator; COI, charge-ordered insulator (from ref 67). Figure 20. Phase diagram showing the prevalence of charge- ordered (CO) and ferromagnetic states in Ln;-,A,MnO3 de- pending on the weighted average radius of the A-site cation, ra, or the e, bandwidth.
Figure 21. Magnetic and electronic phase diagrams of (a) Pri_,Sr,MnO3 and (b) Pri-,Ca,MnO;: PMI, paramagnetic insulator; PMM, paramagnetic metal; CSI, canted spin insula- tor; FMI, ferromagnetic insulator; FMM, ferromagnetic metal; AFMI, antiferromagnetic insulator; CAFMI, canted antifer- romagnetic insulator; COI, charge-ordered insulator (from ref 67). Figure 20. Phase diagram showing the prevalence of charge- ordered (CO) and ferromagnetic states in Ln;-,A,MnO3 de- pending on the weighted average radius of the A-site cation, ra, or the e, bandwidth.
Figure 22. Temperature variation of (a) d(np)/d(T~}), (b) thermopower, (c) specific heat divided by temperature with lattice estimate subtracted, (d) M/H, and (e) sound velocity of La,_,,Ca,MnOs3 (x = 0.65). Note the charge ordering transition temperature, T.. = 260 K (from ref 75).
Figure 22. Temperature variation of (a) d(np)/d(T~}), (b) thermopower, (c) specific heat divided by temperature with lattice estimate subtracted, (d) M/H, and (e) sound velocity of La,_,,Ca,MnOs3 (x = 0.65). Note the charge ordering transition temperature, T.. = 260 K (from ref 75).
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EngineeringCondensed Matter PhysicsMaterials ScienceMaterials ChemistryGiant MagnetoresistanceCurie temperatureColossal MagnetoresistanceRare earth compounds
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