Extended Linear Chain Compounds

Linear chain substances span a large cross section of contemporary chemis­ try ranging from covalent polymers, organic charge transfer complexes to nonstoichiometric transition metal coordination complexes. Their common­ ality, which coalesced intense interest in the theoretical and experimental solid-state-physics/chemistry communities, was based on the observation that these inorganic and organic polymeric substrates exhibit striking metal-like electrical and optical properties. Exploitation and extension of these systems has led to the systematic study of both the chemistry and physics of highly and poorly conducting linear chain substances. To gain a salient understanding of these complex materials rich in anomalous anisotropic electrical, optical, magnetic, and mechanical properties, the convergence of diverse skills and talents was required. The constructive blending of traditionally segregated disciplines such as synthetic and physical organic, inorganic, and polymer chemistry, crystallography, and theoretical and experimental solid state physics has led to the timely devel­ opment of a truly interdisciplinary science. This is evidenced in the contri­ butions of this monograph series. Within the theme of Extended Linear Chain Compounds, experts in important, but varied, facets of the discipline have reflected upon the progress that has been made and have cogently summarized their field of specialty. Consequently, up-to-date reviews of numerous and varied aspects of "extended linear chain compounds" has developed. Within these volumes, numerous incisive contributions covering all aspects of the diverse linear chain substances have been summarized. I am confident that assimilation of the state-of-the-art and clairvoy­ ance will be rewarded with extraordinary developments in the near future.

1. The Infinite Linear Chain Compounds Hg3-? AsF6 and Hg3-?SbF6.- 1. History and Introduction.- 2. Chemistry.- 3. Room-Temperature Structure (D Phase).- 4. Structure-Related Properties.- 4.1. Composition.- 4.2. Extrusion of Mercury.- 4.3. Thermal and Hydrolytic Decomposition.- 5. Electrical Resistivity.- 6. Low-Temperature Structure: Ordering of the Mercury Chains.- 6.1. Theoretical Considerations.- 6.2. Experimental Observations.- 7. Dynamical Properties.- 7.1. Lattice Dynamics.- 7.2. Elastic Constants.- 7.3. Specific Heat.- 8. Superconducting Properties.- 9. Electron Properties.- 9.1. De Haas-van Alphen Effect and Fermi Surface.- 9.2. Induced Torque.- 9.3. Magnetoresistance.- 9.4. Nuclear Magnetic Resonance.- 9.5. Thermoelectric Power.- 9.6. Optical Reflectance.- 10. Summary.- Notation.- References.- 2. The Synthesis and Static Magnetic Properties of First-Row Transition-Metal Compounds with Chain Structures.- 1. Introduction.- 1.1. General Magnetic Interaction Hamiltonian.- 1.2. Isotropic Heisenberg Interaction.- 1.3. Anisotropic Heisenberg Interaction.- 1.4. The XY (or Planar Heisenberg) Interaction.- 1.5. The Ising Interaction.- 1.6. Effects of Zero-Field Splitting.- 2. Chain Compounds of Titanium.- 3. Chain Compounds of Vanadium.- 3.1. Vanadium Chain Compounds of the AVX3 Type.- 3.2. Vanadyl Chains.- 3.3. BaVS3.- 4. Chain Compounds of Chromium.- 4.1. Crystal-Field Background for the Chromium Ion.- 4.2. Additional Theoretical Considerations for Chromium Chains.- 4.3. Chromium Chain Compounds with Halide Bridges of the AMX3 Type.- 4.4. CsCrF4: An Infinite Antiferromagnetic Triple Chain.- 4.5. Poly(chromiumphosphinates).- 5. Chain Compounds of Manganese.- 5.1. An Isotropie Antiferromagnetic Linear Chain, [(CH3)4N][MnCl3].- 5.2. A Manganese Linear Chain without 0, D > 0, D/J = 0.9.- 8.4. NiCl2 · 2H2O: A Compound with J > 0, D < 0, ? D ? /J = 0.08.- 8.5. CsNiCl3: A Compound with J 0, D/J = 0.05.- 8.6. RbNiCl3: A Compound with J < 0, D < 0, D/J = 0.08.- 8.7. Ni(N2H5)2(SO4)2: A Compound with J < 0, D < 0, ? D ? / ? J ? = 9.2.- 8.8. Ni(C4O4)(C3N2H4)2(H2O)2: A Compound with D > 0, D > 4?J ?.- 9. Chain Compounds of Copper.- 9.1. Theoretical Models Applicable for Copper Chains.- 9.2. Antiferromagnetic Exchange in a Uniformly Spaced Linear Chain, Catena-di-?-chloro-bis(pyridine)copper(II).- 9.3. Ferromagnetic Exchange Coupling in the Uniformly Spaced Copper(II) Chain Compounds, Cu(DMSO)Cl2 and Cu(TMSO)Cl2.- 9.4. Alternatingly Spaced Chain Compounds.- 9.5. A Chain Compound with a Ladderlike Structure, Catena-trichlorohydraziniumcopper(II).- 9.6. A Copper Chain Compound Bridged by an Extended Pi System Ligand, Copper Pyrazine Nitrate.- 9.7. Chain Compounds without Ligand Bridges.- 10. Summary.- Notation.- References.- 3. Ferromagnetism in Linear Chains.- 1. Introduction.- 2. Background.- 3. Synthetic Strategies.- 4. Magneto-Structural Correlations in Dimeric Systems.- 5. Theoretical Predictions.- 5.1. Static Properties of the S = 1/2 Ferromagnetic Chain.- 5.2. Static Properties of the S = 1 Ferromagnetic Chain.- 6. Recent Progress in Ferromagnetic Linear Chain Systems.- 6.1. Copper(II) Salts.- 6.2. Nickel(II) Salts.- 6.3. Cobalt(II) Salts.- 6.4. Iron(II)Salts.- Notation.- References.- 4. Magnetic Resonance in Ion-Radical Organic Solids.- 1. Introduction.- 2. Triplet Spin Excitons: Dimerized Ion-Radical Stacks.- 2.1. Wurster’s Blue Per chlor ate, (TMPD)(C1O4), Revisited.- 2.2. Supermolecular Radicals: Complex TCNQ Salts.- 2.3. Charge-Transfer and ?-Bonded Dimers.- 3. Charge-Transfer Complexes with Mixed Regular Stacks.- 3.1. Paramagnetism and Ionicity of (TMPD)(TCNQ).- 3.2. Structure of Spin Excitations.- 4. NMR Studies of Ion-Radical Solids.- 4.1. Nuclear Spins as Solid-State Probes.- 4.2. Internuclear Dipolar Local Fields.- 4.3. Electronic Local Fields.- 4.4. Dimensionality of Spin Dynamics.- 5. Paramagnetism of Ion-Radical Solids.- 5.1. Organic Conductors: Susceptibility of (TTF)(TCNQ).- 5.2. EPR Linewidth of Organic Conductors.- 5.3. Random Exchange Heisenberg Antiferromagnetic Chains.- 5.4. Atomic Limit and Spin Dynamics.- 6. Discussion.- Notation.- References.- 5. Salts of 7,7,8,8-Tetracyano-p-quinodimethane with Simple and Complex Metal Cations.- 1. Introduction.- 2. Alkali and Ammonium Salts of 7,7,8,8-Tetracyano-p-quinodimethane.- 2.1. Preparation.- 2.2. Structural Investigations.- 2.3. Phase Transitions.- 2.4. Electrical Conductivity and Other Transport Properties.- 2.5. Magnetic Measurements.- 2.6. Nuclear Magnetic Resonance.- 2.7. Vibrational, Electronic, and Photoelectron Spectra.- 2.8. Pressure Effects.- 2.9. Miscellaneous.- 3. 7,7,8,8-Tetracyano-q-quinodimethane Salts of Other Simple Metal Ions.- 4. 7,7,8,8-Tetracyano-p-quinodimethane Salts of Metal Complexes and Organometallic Compounds.- 4.1. Salts Containing Main Group Metals.- 4.2. TCNQ Salts or Adducts of Transition-Metal Complexes.- 5. Applications.- 6. Summary.- Notation.- References.- 6. Linear Chain 1,2-Dithiolene Complexes.- 1. Introduction.- 2. Chemistry of the 1,2-Dithiolene Ligand and Its Linear Complexes.- 2.1. Aliphatic 1,2-Dithiolene Complexes: [M(S2C2R2)2]Z Type.- 2.2. Aromatic 1,2-Dithiolene Complexes: [M(S2Ar)2]Z Type; z= 1? and 2?.- 3. Molecular and Electronic Structures of Metal 1,2-Dithiolene Complex Molecules.- 3.1. Molecular Structures.- 3.2. Electronic Structures.- 4. Linear Chains of Metal 1,2-Dithiolene Complex Molecules.- 4.1. Structural Data.- 4.2. Magnetic Properties.- 4.3. Electrical Properties.- 5. Conclusions.- Notation.- References.- 7. The Spin-Peierls Transition.- 1. Introduction.- 1.1. Introductory Remarks.- 1.2. Background.- 2. Theory of the Spin-Peierls Transition.- 2.1. Physical Ideas and Formulations of the Problem.- 2.2. Mean-Field Results.- 2.3. Beyond Mean-Field Solutions.- 2.4. Effects of External Probes: Magnetic Field, Pressure, and NMR.- 2.5. Relationship to Regular Peierls Transition.- 3. Experimental Systems.- 3.1. Tetrathiafulvalenium Bis-Dithiolene Meta-Compounds.- 3.2. (Methylethylmorpholinium)(Bis-7,7,8,8-Tetracyano-p-quinodimethamide), MEM(TCNQ)2.- 3.3. Other Possible Spin-Peierls Systems.- 3.4. High-Magnetic-Field Experiments.- 3.5. Pressure Experiments.- 4. Conclusions and Summary.- Notation.- References.- 8. Polypyrrole: An Electrochemical Approach to Conducting Polymers.- 1. Introduction.- 2. PyrroleBlack.- 3. Electrochemical Preparation of Polypyrrole.- 4. Free-Standing Films.- 5. Electrochemical Properties of Thin Films.- 6. N-Substituted Polypyrroles.- 7. AnionVariation.- 8. Applications.- References.- 9. Compendium of Synthetic Procedures for One-Dimensional Substances.- 1. Introduction.- 2. Organic Materials.- 2.1. Electron-Donor Molecules.- 2.2. Electron-Acceptor Molecules.- 2.3. Organic Charge-Transfer Complexes.- 3. Inorganic Materials.- 3.1. Metal Dithiolenes.- 3.2. Partially Oxidized Metal-Chain Systems.- 3.3. Polymercury Cation Chain Systems.- 4. Polymeric Materials.- 4.1. Poly(sulfurnitride)[Polythiazyl],(SN)x.- 4.2. Polyacetylene, (CH)x.- 4.3. Polypyroles.- References.- 10. Structural, Magnetic, and Charge Transport Properties of Stacked Metal Chelate Complexes.- 1. Introduction.- 2. Integrated Stack Crystals.- 2.1. General Features.- 2.2. Metal Complex D+p or A?q, Organic Molecule A?q or D+p.- 2.3. Mixed-Metal Complexes.- 3. Segregated Stack Crystals, Integral Oxidation State Metal Complexes.- 3.1. General Features.- 3.2. Metal Complex Not Stacked.- 3.3. Metal Complex Stacked.- 3.4. Structurally Uncharacterized Systems.- 4. Segregated Stack Crystals, Nonintegral Oxidation State Metal Complexes.- 4.1. General Features and Methods of Characterization.- 4.2. The ?,?-Dionedioximates.- 4.3. The Porphyrins and Derivatives.- 4.4. Other Metallomacrocycles.- 5. Future Directions.- References.