Chemical Mössbauer Spectroscopy. Questo articolo non è disponibile.Chemical Mössbauer Spectroscopy

The past twenty five years - roughly the period from 1960 to 1985 - have been by all measures among the most exciting and challenging times of our science. The increasing sensitivity of chemical instrumentation, the introduction of the routine use of computers for data reduction and of microprocessors for instrumental control, the wide-spread utilization of lasers, and the disappearance of traditional disciplinary boundaries between scientific fields are but a few of the examples one could cite to support the introductory contention. Almost all of these developments have had their impact on the development of Mossbauer Effect Spectroscopy into a technique par excellence for the elucidation of problems in all areas of chemistry and its associated sister sciences. Indeed, because this spectroscopy is based on fundamental phenomena in nuclear physics, is described in terms of the theory of the solid state and structural chemistry, is useful in the understanding of chemical reactivity and biological phenomena, and can serve to supplement information developed by many other experimental techniques, it has provided an unparalleled opportunity for the exchange of ideas among practitioners of a very wide variety of subfields of the physical and biological sciences. The present collection of contributions is the direct result of such an interaction.

I. Aspects of Organoiron Mossbauer Spectroscopy.- The Mossbauer Experiment.- Isomer Shift.- Electric Quadrupole Interaction.- Oxidation State and Bonding.- Six Coordination.- Five Coordination.- Four Coordination.- Organoiron Complexes.- Binary Carbonyls.- Mixed Metal Tetracarbonylferrates.- pi Complexes of Iron.- Iron cyanide complexes.- Acknowledgments.- II. Spin Transition in Iron Compounds.- Fe(phen)2(NCS)2.- Spin Transition Characteristics.- Effect of Crystal Quality.- Effect of Metal Dilution.- Effect of a Magnetic field on the Spin Transition.- Fe(2-pic)3X2·Sol.- Unusual Spin transition Properties.- Crystal Structure.- Anion Influence.- Effect of Isotopic Exchange.- Effect of Metal Dilution.- The EILE Model (Elastic Interaction and Lattice Expansion).- Effect of Applied Pressure.- LIESST (Light Induced Spin State Trapping).- First observation.- LIESST in other Spin Crossover Complexes.- Conclusion.- Acknowledgment.- III: Zero and High Field Mossbauer Spectroscopy Studies of the Magnetic Ordering Behavior of One, Two and Three Dimensional Systems.- Hyperfine Interactions.- Effective Magnetic Fields.- Combined Nuclear Zeeman and Quadrupole Splitting.- Contributions to the Internal Hyperfined Field.- Single Ion Zero Field Splitting.- Intensities-Single Crystal Studies.- High Field Massbauer Spectra.- Antiferromagnets.- Ferromagnets.- Ferrimagnets.- Some Recent Applications.- Isomeric Ordered Materials.- Complex Bimetallic Salts.- 2D Magnet Based Layers.- Conclusion and Acknowledgment.- IV: A Mossbauer Effect and Magnetic Study of Fe2(SO4)3 and Fe2(MoO4)3, Two L-type Ferrimagnets.- Crystal and Magnetic Structures.- Mossbauer-Effect Spectral Results.- Magnetic Susceptibility Studies.- Magnetic Ordering Model.- Acknowledgments.- V: Biomineralization of Fe3O4 in Bacteria.- Mossbauer Spectroscopy of Ferritin.- Mossbauer Spectroscopy of Magnetotactic Bacteria.- Conclusion.- Acknowledgment.- VI: Mossbauer Spectroscopy of Intercalation Compounds.- Structure and Chemistry of Intercalated Materials.- General Aspects of Spectroscopy.- Studies of Structure and Bonding.- Charge Density Waves.- Charge Transfer Between Guest and Host.- Metal Cation Insertion Compounds.- Lewis Base Intercalation.- Lewis Acid Intercalation.- Lattice Dynamical Properties.- Debye Temperature and Effective Vibrating Mass.- Influence of Guest Species.- Binding of Guest Species.- Vibrational Anisotropies.- Magnetic Phenomena.- Magnetic Phenomena of the Host Lattice.- Transition Metal Dichalcogenider.- Ordering in Fe0C1.- Magnetic Ordering of Guest Species.- Summary and Acknowledgments.- VII: Hot-Atom Chemistry and Trapped Species.- After Effects Associated with Nuclear Decay.- Range Involved in After Effects.- Radical Species Produced around the Decaying Atom.- Local Radiation Damage.- Application to Blanket Materials.- VII: Structure, Bonding, and the Mossbauer Lattice Temperature.- Fundamental Equations.- Some Applications to Inorganic Systems.- Lattice Dynamics of FeTi.- Lattice Dynamics of LiFeSnO4.- Lattice Djmamics of BaSnO3.- Lattice Dynamics of Organometallics.- Summary and Acknowledgments.- IX: Mossbauer Spectroscopy of Soils and Sediments.- Reviews, and General Papers.- Synthetic and Natural Single Phases.- Goethite, ? FeOOH.- Hematite, ? Fe2O3.- Akaganeite, ? FeOOH.- Lepidocrocite, ? FeOOH.- Clay Minerals.- Sediments.- Humic Acid Complexes and Ferrihydrite.- Example Soil Clays and Conclusions.- X: Mossbauer Studies of Liquid Crystals.- Abstract.- Liquid Crystals.- Mossbauer Studies in Liquid Crystals.- Initial Observations.- Orientation Effects.- Temperature Effects.- Iodine Mossbauer Spectroscopy.- Liquid Crystal-label Complexes.- Lyotropic Liquid Crustals.- Conclusions and Projections.- XI: Organotin-119m Mossbauer Spectroscopy: The First Quarter Century.- Organotin Chemistry.- Tin Mossbauer Spectroscopy.- Applications.- Determination of Oxidation State.- Finger Printing.- Tin Atom Site Symmetries.- The ? Value and Coordination Number.- The Point Charge Model.- Lattice Dynamics.- The Next 25 Years.- XII: Mossbauer Spectroscopy of Iodine.- Isomer Shift Calibration.- Chemical Bond Information.- Miscellaneous Compounds.- Linear Iodine Chains.- Radiogenic Systems.- Tellurium Halides.- Heusler Alloys.- Experiments with Implanted Sources.- Isomer Shift.- Quadrupole Splitting, Recoilles Fraction.- XIII: Mossbauer Spectroscopy of Antinomy Compounds.- Experimentation.- Applications.- Ph4SbX Structures.- Dithiocarbamate Compleses.- Rsb(Et2dtc)2.- Sb(Bu2dtc)2L.- Ph2Sb(Et2dtc)2.- Interpretation of Mossbauer Parameters.- Self Consistent Atomic Orbital Calculations.- Point Charge Models.- Molecular Orbital Calculations.- Other Models.- XIV: Rare-Earth Mossbauer Studies of Chemical Problems.- Rare Earth Mossbauer Spectroscopy.- Chemical Bonding in Rare Earth Compounds.- Lattice Vibrational Anisotropy.- Conversion Electron Mossbauer Spectroscopy.- Conclusions.- XV: Chemical Aspects of 237Np Mossbauer Spectroscopy.- Description of 237Np Mossbauer Effect.- Neptunium (VII).- Proposed NPOCI52- Compounds.- Np(C8H8)I·xTHF.- Np(V)-Transition Metal Ion Complexes.- [(CH3)4N]2NpCl6 and [(C2H5)4N]2NpCl6.- Convalency of Np(IV) Organometallic Compounds.- Acknowledgment.