Properties of Perovskites and Other Oxides

Preface......Page 8
Contents......Page 10
Introduction......Page 16
IA. EPR of Transition-Metal Ions in SrTi03......Page 20
I. Introduction......Page 22
II. Properties of SrTi03......Page 23
III. Theory......Page 25
IV. The resonance spectrometer......Page 31
The samples......Page 35
Measurements at room temperature......Page 36
Determination of the Stark splitting......Page 39
Discussion of the room-temperature results......Page 40
Results at 80 oK and their explanation......Page 44
VI Acknowledgements......Page 46
References......Page 47
IA2. Electron paramagnetic resonance of manganese IV in SrTi03, K.A. Muller, Phys. Rev. Lett. 2, 341-343 (1959)......Page 49
IA3. Resonance paramagnetique du Cr3+ dans des monocristaux de SrTi03, KA. Muller, Arch. Sci. (Geneve) 11, 150--152 (1958)......Page 52
IA4 . Photo chromic Fe5+ (3d3 ) in SrTi03, evidence from paramagnetic resonance, KA. Muller, Th. von Waldkirch, W. Berlinger and B.W. Faughnan, Solid State Commun. 9, 1097-1101 (1971)......Page 55
REFERENCES......Page 58
1. Introduction......Page 60
2. Experiment and results......Page 61
3. Assignment of the new EPR spectrum to C04+......Page 62
4. Determination of the orbital reduction factor k and radial electron distribution (r-3)......Page 65
5. Linewidth anisotropy and strain coupling......Page 66
6. The dynamic Jahn-Teller effect......Page 69
8. Conclusion......Page 70
References......Page 71
IA6 . Paramagnetic Ru5+ and Ru3+ centers in Ti02:Ru, KW. Blazey, KA. Muller, W. Berlinger, P. Triggs and F. Levy, Solid State Commun. 54, 1039-1041 (1985)......Page 72
REFERENCES......Page 74
2. Creation and identification of the centre......Page 75
3. d spin and charge delocalisation......Page 77
4. The V2+ and V3+ energy levels near the SrTi03 conduction band......Page 78
References......Page 81
IB. Hyperfine and Superhyperfine Interactions......Page 82
I. INTRODUCTION......Page 83
ll. EXPERIMENTAL RESULTS......Page 84
III. CATION-SUPERHYPERFlNE STRUCTURE......Page 85
A. g Shift......Page 89
B. D Parameter......Page 90
APPENDIX: ESTIMATE OF AN UPPER LIMIT OF THE g SHIFT......Page 91
I. INTRODUCTION......Page 92
2. EXCHANGE POLARIZATION OF THE BONDING ORBITALS......Page 96
3. UNPAIRED s-DENSITY AT MANGANESE NUCLEUS......Page 97
(a) General remarks......Page 99
(b) Numerical estimates......Page 100
(c) 3d3 in octahedral surroundings......Page 101
5. CONCLUSIONS......Page 102
REFERENCES......Page 103
Appendix: Table 1......Page 104
IC. Unusual Phenomena in the Linewidth and Defect Centers......Page 106
IC1 . The temperature dependence of the linewidth of iron group ions in MgO, A.M. Stoneham, KA. Muller and W. Berlinger, Solid State Commun. 10, 1005-1008 (1972)......Page 107
REFERENCES......Page 110
I. INTRODUCTION......Page 111
A. TA. Model of Center......Page 113
B. Electric Field Effects......Page 116
C. Orthorhombicity of Centers......Page 117
VI. COMPARISON WITH OTHER NONCENTROSYMMETRIC CENTERS IN PEROVSKlTE-TYPE CRYSTALS......Page 118
ACKNOWLEDGMENTS......Page 119
IC3. Holes trapped near Mg2+ and A13+ impurities in SrTi03, O.F. Schirmer, W. Berlinger and KA. Muller, Solid State Commun. 18, 1505-1508 (1976)......Page 121
REFERENCES......Page 123
2. Experimental details......Page 125
3. Results......Page 126
4.1. Characterization of the centre......Page 129
4.2. Electric field and stress effects......Page 130
References......Page 133
II. EXPERIMENTAL DETAILS......Page 135
A. Electron spin resonance spectra......Page 136
B. Analysis of ESR data......Page 137
2. Na hyperfine interaction......Page 138
C. Thermal stability of the neutral state of the alkali acceptors......Page 139
E. Optical absorption......Page 140
F. Reorientation of the Na+-0- axes under uniaxial stress......Page 141
IV. DISCUSSION......Page 142
APPENDIX: JAHN-TELLER EFFECT OF THE 0-    ORBITALS......Page 143
IC6 . Characterization of particle orientations in ceramics by electron paramagnetic resonance, F. Mehran, K.A. Muller, W.J. Fitzpatrick, W. Berlinger and M.S. Fung, J. Am. Ceram. Soc. 64, C129-C130 (1981)......Page 145
References......Page 146
IIA. The Observation of Me-Va Centers......Page 148
Reference......Page 149
I. INTRODUCTION......Page 150
The g Values of Ions of Half-Integral Spin (S   ) in a Strong Positive Axial Field......Page 151
IlI. EXPERIMENTAL RESULTS......Page 152
IV. DISCUSSION......Page 153
ACKNOWLEDGMENTS......Page 154
1. INTRODUCTION......Page 155
II. EXPERIMENTAL RESULTS AND IDENTIFICATION OF RESONANCE LINES......Page 156
III. THEORETICAL ANALYSIS......Page 160
A. Rotational Parameter     (T)......Page 162
C. Application of the Center for Structural Studies......Page 163
ACKNOWLEDGMENTS......Page 164
I. INTRODUCTION......Page 166
II. PARAMAGNETIC-RESONANCE SPECTRA......Page 167
III. 9 VALUES FOR 3d7 AND 3d9 CONFIGURATIONS......Page 170
B. g Shifts......Page 171
C. Titanium Superhyperfine Interaction......Page 172
B. g Shifts, SHS, and Linewidth......Page 173
A. Low-Spin NiH Spectra in KTa03......Page 174
VIII. SUMMARY AND CONCLUSIONS......Page 175
ACKNOWLEDGMENTS......Page 176
IIA4 . Electron spin resonance and optical identification of Fe4+ -Vo in SrTi03, O.F. Schirmer, W. Berlinger and KA. Muller, Solid State Commun. 16, 1289-1292 (1975)......Page 177
REFERENCES......Page 180
I. INTRODUCTION......Page 181
II. EXPERIMENTAL PROCEDURE......Page 182
IV. Mn2+-Vo CENTER......Page 183
V. Mn3 +-Vo......Page 186
IIB. The Structure of the Me-Vo Centers......Page 189
II. NEWMAN LINEAR-SUPERPOSITION MODEL......Page 190
A. b2, for Fe3+ and Mn2+ in oxide compounds......Page 191
B. b2 for Fe3+ in fluoride perovskite compounds......Page 192
IV. LOCAL ENVIRONMENT OF M.Vo PAIR CENTERS IN OXIDE PEROVSKITE COMPOUNDS......Page 193
A. Axial MgO and srO centers......Page 196
B. Strong axial Fe3+ centers in some fluorine perovskite compounds......Page 197
C. Spin-Hamiltonian parameter b......Page 199
APPENDIX B: AXIAL CENTER OF Mn2+ IN KTa03......Page 200
IIB2 . Structure of the Cr3+ -Vo centers in WO3, KA. Muller, J. Phys. Soc. lpn. 55, 719-722 (1986)......Page 202
References......Page 205
1. Introduction......Page 206
2.1. Superposition model for S < 2......Page 208
2.2. Stress-induced spin-Hamiltonian terms......Page 209
3. Experiments......Page 210
4.1. Dependence on b2(R) for Cr3 +......Page 213
4.2. Charge and size misfits......Page 215
4.3. Cr3+ substitution for a three-valent host ion......Page 216
Acknowledgments......Page 218
References......Page 219
2. Experiment and Results......Page 220
References......Page 222
IIC. The Axial Gd3+ -O2- Center in RbCaF3......Page 224
Results and discussions......Page 225
References......Page 226
III. Photochromism......Page 228
Reference......Page 229
III1. Identification of charge-transfer bands by EPR conversion-rate measurements, K.A. Muller, in Magnetic Resonance in Condensed Matter — Recent Developments, eds. R. Blinc and G. Lahajnar (Ljubljana, 1977), pp. 663-679......Page 230
1. Introduction......Page 231
2. The EPR Conversion-Rate Method......Page 232
3. Results in SrTi03......Page 235
4. Interpretation......Page 242
References......Page 246
III2. Identification of Fe4+ and Fe5+ charge-transfer photochromic absorption bands in SrTi03, KW. Blazey, O.F. Schirmer, W. Berlinger and KA. Muller, Solid State Commun. 16, 589-592 (1975)......Page 247
REFERENCES......Page 249
II. EXPERIMENT......Page 251
B. Ni 3 +,vo +e acceptor charge transfer......Page 254
E. Transfer rates between Ni3+-V0 +2e and Ni3+-V0 +e......Page 255
IV. SUMMARY......Page 256
IV. The Jahn-Teller Effect......Page 258
Reference......Page 259
IV 1. Observation of the Jahn–Teller splitting of three-valent d7 ions via Orbach relaxation, U. Hochli and KA. Muller, Phys. Rev. Lett. 12, 730-733 (1964)......Page 260
1. INTRODUCTION: THE STATIC EFFECT IN OCTAHEDRAL COORDINATION......Page 264
2. QUANTITATIVE ANALYSIS......Page 268
3.1. Motion on the lower potential branch: g values, hyperfine interaction, T2 mechanism......Page 271
3.2. T1 mechanism: evidence for the existence of Slonczewski modes on the upper potential branch......Page 274
REFERENCES......Page 279
IV3. V4+ in SrTi03 : A Jahn-Teller impurity, Th.W. Kool and M. Glasbeek, Solid State Commun. 32, 1099-1101 (1979)......Page 281
REFERENCES......Page 283
1. Introduction......Page 284
3. Results......Page 285
4. Discussion......Page 287
References......Page 292
I. INTRODUCTION......Page 293
II. Ni3+ RESONANCE IN TETRAGONAL PHASE......Page 294
III. THEORY......Page 295
IV. COMPARISON OF THEORY WITH EXPERIMENT......Page 296
ACKNOWLEDGMENTS......Page 299
II. POLARONS......Page 300
III. EXPERIMENTAL DETAILS......Page 301
IV. INTRODUCTORY EXAMPLE: JT EFFECT OF MO5+ IN BT......Page 302
A. Small polarons......Page 303
B. Intermediate polarons......Page 305
D. Further observations......Page 307
VI. TI3+ POLARONS BOUND TO AN OXYGEN VACANCY......Page 308
VII. DISCUSSION......Page 309
ACKNOWLEDGMENTS......Page 310
1. Introduction......Page 312
2. Theoretical background of the E   e JT effect......Page 313
4.1. Ni+ (3d9)......Page 316
4.2. Rh2+ (4d7)......Page 320
4.3. Pt3+ (5d7 )......Page 321
5. Off-center Fe5+......Page 323
6. Conclusion......Page 325
References......Page 326
IV8 . Theory of a structural phase transition induced by the Jahn-Teller effect, H. Thomas and K.A. Muller, Phys. Rev. Lett. 28, 820- 823 (1972)......Page 327
V. Non-Kramers Ions......Page 332
I. INTRODUCTION: SPIN-1/2 FORMALISM......Page 334
II. SPIN-I FORMALISM......Page 335
ACKNOWLEDGMENTS......Page 338
1. Introduction......Page 339
2. The Hamiltonian for a non-Kramers doublet......Page 340
3. Lineshapes......Page 341
4. Experimental results......Page 343
Acknowledgment......Page 347
References......Page 348
VIA. Off-Center Ions......Page 350
2. Experimental results......Page 352
3. Discussion......Page 353
References......Page 355
VIA2 . Tetrahedrally coordinated Cr5+ in SrTi03, K.A. Muller, K.W. Blazey and Th.W. Kool, Solid State Commun. 85, 381-384 (1993)......Page 356
References......Page 359
1. Introduction......Page 360
3. Results and discussion......Page 361
References......Page 365
References......Page 366
II. MATERIALS AND METHODS......Page 367
A. Cr3+ site symmetry......Page 368
B. Cr3+-oxygen vacancy complex......Page 369
C. Electron localization: Suppression of the conducting state......Page 371
ACKNOWLEDGMENTS......Page 373
VIlB. Oxide Ferroelectrics (Sec. 1.4)......Page 376
VIID. Experiments on Multicritical Points (Sec. 1.6)......Page 378
VIlE. Order–Disorder Transitions (Sec. 1.7)......Page 380
VIlF. Incommensurate Phases (Sec. 1.8)......Page 381
1. Introduction......Page 383
References......Page 390
1.1 Introduction......Page 391
1.2 Methodological Aspects......Page 392
1.2.1 Choice of Paramagnetic Ions or Radicals......Page 393
1.2.2 The Spin-Hamiltonian Formalism......Page 394
1.2.3 Site Determination......Page 397
1.2.4 Ligand-Field Parameters and the Superposition Model......Page 398
1.3.1 Standard Equipment......Page 402
1.3.2 Special Requirements for Investigations of Structural Phase Transitions......Page 404
1.4 Oxide Ferroelectrics......Page 408
1.4.1 EPR of Fe3+ and Gd3+ in Cubic and Tetragonal BaTi03......Page 409
1.4.2 Fe3+ and Gd3+ Spectra in Orthorhombic and Rhombohedral BaTi03......Page 411
1.4.3 Cr 3+ in BaTi03 : A Centered Ion with a Flat Local Potential......Page 413
1.4.4 Mn4+ on Ferroelectric Ti4+ Sites: Evidence for Intrinsic Low-Frequency Dynamics......Page 416
1.4.5 The EPR Parameter a of Fe3+ in BaTi03 and KNb03......Page 418
1.5.1 The Cubic-to-Tetragonal Transformation in SrTi03......Page 421
1.5.2 The Cubic-to-Trigonal Phase Transition in LaAI03......Page 424
1.5.3 Critical Phenomena......Page 427
1.5.4 Order-Parameter Behavior in PrAIO3......Page 431
1.6.1 Introduction......Page 433
1.6.2 Bicritical Points in SrTi03 and LaAI03......Page 434
1.6.3 Phases Induced by Competing Forces......Page 436
1.6.4 Uniaxial Stress Effects on the Antiferrodistortive Transition of RbCaF3 and Multicritical Behavior......Page 438
1.7 Order-Disorder Transitions......Page 445
1.7.1 NH! Ordering in Pure Crystals......Page 447
1.7.2 NH! Ordering in Mixed Crystals: RbxNH4(I-x)AIF4......Page 449
1.7.3 Room-Temperature Phases of Mixed Crystals......Page 451
1.8 Incommensurate Phases......Page 452
1.8.1 EPR of Charge-Compensated Defects in the INC Phases of ThBr4 and ThCI4:Gd3+......Page 454
1.8.2 EPR of Mn2+ in Doped Betaine Calcium Chloride Dihydrate (BCCD) and Substitutional Probes......Page 458
1.8.3 Incommensurate Phases in Diphenyl Studied via a Triplet-State Spin Probe......Page 465
References......Page 467
I. INTRODUCTION......Page 473
A. Mn4+ EPR spectra at X and Q bands......Page 474
B. Linewidth......Page 476
A. Anisotropy of broadening......Page 477
C. Orthorhombic phase......Page 479
ACKNOWLEDGMENTS......Page 480
VIl4 . Photochromic Fe5+ in non-cubic local fields in SrTi03, Th.W. Kool and M. Glasbeek, Solid State Commun. 22, 193- 197 (1977)......Page 481
REFERENCES......Page 485
VIII. Dipolar and Quantum Paraelectric Behavior......Page 486
Reference......Page 487
VIll1. Dipolar behaviour in KTa0.9Nbo.1O3, R. Kind and K.A. Muller, Commun. Phys. 1, 223-228 (1976)......Page 489
References......Page 494
VIII2. Non-Curie–Weiss behavior in ferroelectric perovskites, H. Bilz, R. Migoni, G. Meissner and K.A. Muller, Abstract Booklet, 4th European Meeting on Ferroelectricity, Portoroz, Yugoslavia (J. Stefan Institute, Ljubljana, 1979) p. 32......Page 495
I. INTRODUCTION......Page 496
II. EXPERIMENTAL......Page 497
III. EXISTENCE OF A QUANTUM-MECHANICAL PARAELECTRIC STATE......Page 499
A. Static considerations and phenomenological soft-mode theories......Page 500
B. Comparison to recent dynamic microscopic theory......Page 501
V. CONCLUSIONS......Page 502
APPENDIX: THE DYNAMIC MEAN-FIELD APPROACH......Page 504
VIII4 . Sr1-xCax Ti03: An XY quantum ferroelectric with transition to randomness, J.G. Bednorz and K.A. Muller, Phys. Rev. Lett. 52, 2289-2292 (1984)......Page 506
VIII5. Domain state properties of the random-field xy-model system Srl-xCax Ti03, W. Kleemann, F.J. Schafer, K.A. Muller and J.G. Bednorz, Ferroelectrics 80, part III, 297-300 (1988)......Page 510
REFERENCES......Page 513
I. Introduction......Page 514
II. Experimental......Page 515
1. Considerations related to the EPR data......Page 516
2. Can there be a novel quantum state?......Page 517
IV. Conclusions......Page 518
References......Page 519
Note added after acceptance of the paper......Page 520
IX. Electronic Structure of SrTi03......Page 522
IX1 . Valance-band splitting of SrTi03, K.W. Blazey, M. Aguilar, J.G. Bednorz and K.A. Muller, Phys. Rev. B 27, 5836-5838 (1983)......Page 523
ACKNOWLEDGMENT......Page 524
II. EXPERIMENTAL......Page 526
III. RESULTS AND DISCUSSIONS......Page 527
ACKNOWLEDGMENTS......Page 529
XA. Fermi Glasses......Page 530
XA1. Pauli paramagnetism in a Fermi glass, K.A. Muller, T. Penney, M.W. Shafer and W.J. Fitzpatrick, Phys. Rev. Lett. 47, 138-142 (1981)......Page 531
1. Introduction......Page 536
3.1. Chemical analysis and neutron-diffraction experiments......Page 537
3.3. Magnetic susceptibility......Page 538
3.5. Thermal conductivity......Page 539
4. Discussion......Page 540
References......Page 542
References......Page 543
1. Introduction......Page 544
2. Experimental......Page 546
3.1. g-Factors, spin concentrations and linewidths......Page 549
3.2. Relaxation times......Page 558
3.3. Influence of growth conditions and time dependences......Page 560
Acknowledgements......Page 562
References......Page 563
Reference......Page 564
XI1. Inhomogeneous superconducting transitions in granular AI, KA. Muller, M. Pomerantz, C.M. Knoedler and D. Abraham, Phys. Rev. Lett. 45, 832-835 (1980)......Page 565
I. Introduction......Page 569
3. Conductivity Measurements......Page 570
III. Discussion......Page 571
References......Page 572
XI3. Susceptibility measurements support high-Tc superconductivity in the Ba-La-Cu-O system, J.G. Bednorz, M. Takashige and KA. Muller, Europhys. Lett. 3, 379-386 (1987)......Page 574
REFERENCES......Page 579
Note added after acceptance......Page 580
CHANGE IN EXISTING REFERENCE:......Page 581