Landolt-Börnstein numerical data and functional relationships in science and technology. Group 3, Condensed matter. Vol. 27, Magnetic properties of non-metallic inorganic compounds based on transition elements. Subvol. J3, Halide Perovskite-type layer st

The magnetic properties of halides have been compiled in subvolume 27J. The third part, **27J3**, contains data on structural and magnetic properties of halide perovskite-type layer structures of the types A2MX4 (monolayer compounds), A3M2X7 (double-layer) and A4M3X10 (triple-layer) where X=F-, Cl-, etc.; M=Mg2+, Cr2+, Mn2+, Zn2+, Cd2+, etc.; and A=K+, Rb+, Cs+, etc. In addition, for X=Cl- and Br- data are presented on compounds where the alkali ions are replaced by n-alkylammonium chains, and also for diammonium compounds where two alkali ions are replaced by divalent alkylene-diammonium ions. A brief sketch of the theory of phase transitions and of the relevant models (2D Ising model, 2D XY-model, 2D Ising spin glass) is also given as well as a comprehensive selection of data on critical properties near the phase transitions. Introductory material 1 Title Page 1 Editor, Author 3 Preface 4 Definitions, units and conversion factors 5 9 Magnetic properties of halides 6 9.12 Halide perovskite-type layer structures R. Geick 6 9.12.1 Introduction 6 9.12.1.1 Characterization of perovskite-type layer structures 6 9.12.1.2 Lattice dynamics: intralayer and interlayer forces 9 9.12.1.3 Comments on notation and units and Table 1 14 Table 1. Symbols and abbreviations 16 9.12.1.4 References for 9.12.1 45 9.12.2 Structural properties 48 9.12.2.1 Structures 48 9.12.2.1.1 General aspects 48 9.12.2.1.2 Easy-axis antiferromagnets 50 9.12.2.1.3 Easy-plane ferromagnets and antiferromagnets 52 9.12.2.1.4 Structures resulting from structural phase transitions 54 9.12.2.1.5 Mixed crystals 57 9.12.2.2 Structural phase transitions 60 9.12.2.2.1 Experimental investigations 60 9.12.2.2.2 Group-theoretical considerations 67 9.12.2.2.3 Structural phase transitions in monoammonium compounds 71 9.12.2.2.4 Model for the phase transitions in monoammonium compounds 74 9.12.2.2.5 Long-chain compounds 79 9.12.2.2.6 Diammonium compounds 80 9.12.2.3 Figures for 9.12.2 and Tables 2 - 4 84 Figs. 2.1 - 2.22 84 Figs. 2.23 - 2.44 95 Table 2. Crystallographic data 108 Table 3. M-X Bond lengths and interlayer distances 125 Table 4. Data about structural phase transitions 136 9.12.2.4 References for 9.12.2 154 9.12.3 Magnetic properties 165 9.12.3.1 Antiferromagnets 165 9.12.3.1.1 Exchange interaction 165 9.12.3.1.2 Mn-compounds, spin-wave theory 166 9.12.3.1.3 Temperature-dependent properties, high temperature series 173 9.12.3.1.4 Double-layer compounds 177 9.12.3.1.5 Ni- and Fe-compounds 178 9.12.3.1.6 Spin-flop transition - AFMR under various conditions 181 9.12.3.1.7 Canted antiferromagnets, weak ferromagnetism 187 9.12.3.1.8 Antiferromagnetic Cu-compounds 190 9.12.3.1.9 Co-compounds 2D Ising model 192 9.12.3.2 Ferromagnets 195 9.12.3.2.1 Cu-compounds 195 9.12.3.2.2 Cr-compounds 202 9.12.3.2.3 Spin-reorientation transitions - FMR under various conditions 208 9.12.3.2.4 Magnetic polaritons 215 9.12.3.2.5 Parallel pumping experiments 217 9.12.3.3 Doped and mixed systems 221 9.12.3.3.1 Paramagnetic centres in diamagnetic host crystals 221 9.12.3.3.2 Magnetic ordering in diluted systems 224 9.12.3.3.3 Spin waves in diluted magnets 230 9.12.3.3.4 Excitations in mixed antiferromagnets 235 9.12.3.3.5 Mixed antiferromagnets with competing anisotropies 241 9.12.3.3.6 Mixed magnets with competing exchange interactions 244 9.12.3.4 Figures for 9.12.3 and Table 5 251 Figs. 3.1 - 3.20 251 Figs. 3.21 - 3.40 259 Figs. 3.41 - 3.60 267 Figs. 3.61 - 3.78 277 Table 5. Data concerning magnetic properties 286 9.12.3.5 References for 9.12.3 336 9.12.4 Critical phenomena 357 9.12.4.1 Static critical behaviour 357 9.12.4.1.1 General 357 9.12.4.1.2 2D Ising model 359 9.12.4.1.3 Experimental determination of alpha 362 9.12.4.1.4 Experimental determination of beta 364 9.12.4.1.5 Experimental determination of gamma, nu and eta 365 9.12.4.1.6 Experimental test of the two-scale-factor universality 368 9.12.4.1.7 2D Heisenberg model 369 9.12.4.1.8 2D XY-model 372 9.12.4.1.9 Crossover phenomena 384 9.12.4.1.10 3D XY-model - structural phase transitions 387 9.12.4.1.11 Critical behaviour near the percolation threshold 390 9.12.4.1.12 Random field effects - random field Ising model 399 9.12.4.1.13 Critical properties of spin glasses - 2D Ising spin glass 406 9.12.4.2 Dynamic critical properties and relaxation 411 9.12.4.2.1 Characteristic frequency from neutron inelastic scattering 411 9.12.4.2.2 Relaxation time - activated dynamics - aging 412 9.12.4.2.3 Spin-wave lineshape of a 2D Heisenberg ferromagnet 418 9.12.4.2.4 2D XY-model: influence of vortices on Sq, omega 420 9.12.4.2.5 Critical broadening of the NMR linewidth 422 9.12.4.2.6 Critical broadening of the EPR linewidth 423 9.12.4.2.7 Critical EPR linewidth due to solitons or due to magnons? 426 9.12.4.2.8 EPR linewidth at high temperatures - spin diffusion 429 9.12.4.2.9 EPR linewidth in mixed crystals 432 9.12.4.3 Figures for 9.12.4 and Table 6 436 Figs. 4.1 - 4.18 436 Figs. 4.19 - 4.34 445 Figs. 4.35 - 4.52 451 Figs. 4.53 - 4.70 459 Table 6. Data about critical behaviour 467 9.12.4.4 References for 9.12.4 494 Introductory material....Pages 1-5 9.12.1 Introduction....Pages 1-42 9.12.2.1 Structures....Pages 43-54 9.12.2.2 Structural phase transitions....Pages 54-77 Figs. 2.1 - 2.22....Pages 78-88 Figs. 2.23 - 2.44....Pages 89-101 Table 2. Crystallographic data....Pages 102-118 Table 3. M-X Bond lengths and interlayer distances....Pages 119-129 Table 4. Data about structural phase transitions....Pages 130-147 9.12.2.4 References for 9.12.2....Pages 148-158 9.12.3.1 Antiferromagnets....Pages 159-188 9.12.3.2 Ferromagnets....Pages 188-213 9.12.3.3 Doped and mixed systems....Pages 213-242 Figs. 3.1 - 3.20....Pages 243-250 Figs. 3.21 - 3.40....Pages 251-258 Figs. 3.41 - 3.60....Pages 259-268 Figs. 3.61 - 3.78....Pages 269-277 Table 5. Data concerning magnetic properties....Pages 278-327 9.12.3.5 References for 9.12.3....Pages 328-348 9.12.4.1 Static critical behaviour....Pages 349-402 9.12.4.2 Dynamic critical properties and relaxation....Pages 402-426 Figs. 4.1 - 4.18....Pages 427-435 Figs. 4.19 - 4.34....Pages 436-441 Figs. 4.35 - 4.52....Pages 442-449 Figs. 4.53 - 4.70....Pages 450-457 Table 6. Data about critical behaviour....Pages 458-484 9.12.4.4 References for 9.12.4....Pages 485-503 In subvolume III/27C2 magnetic and related properties of binary actinide oxides have been compiled. Part 27C1 deals with binary oxides of the lanthanide elements. Magnetic properties of the binary oxides of 3d transition elements are given in subvolume 27 G. Editor: H.p.j. Wijn ; Author: R. Geick. Includes Bibliographical References.