"The Theory of Atomic Spectra", surrrrnanzlllg all that was then known about the quantum theory of free atoms; and in 1961, J.S. Griffith published "The Theory of Transition Metal Ions", in which he combined the ideas in Condon and Shortley's book with those of Bethe, Schlapp, Penney and Van Vleck. All this work, however, was done by physicists, and the results were reported in a way which was more accessable to physicists than to chemists. In the meantime, Carl J. Ballhausen had been studying quantum theory with W. Moffitt at Harvard; and in 1962 (almost simultaneously with Griffith) he published his extremely important book, "Introduction to Ligand Field Theory". This influential book was written from the standpoint of a chemist, and it became the standard work from which chemists learned the quantum theory of transition metal complexes. While it treated in detail the group theoretical aspects of crystal field theory, Carl J. Ballhausen's book also emphasized the limitations of the theory. As he pointed out, it is often not sufficient to treat the central metal ion as free (apart from the influence of the charges on the surrounding ligands): - In many cases hybridization of metal and ligand orbitals is significant. Thus, in general. a molecular orbital treatment is needed to describe transition metal complexes. However, much of the group theory developed In connection with crystal field theory can also be used in the molecular orbital treatment.

Table of Contents:
I. Electronic Structure of Transition Metal Complexes.- Electronic Spectroscopy of Metal-Metal ?-Symmetry Interactions.- Metal Metal Bonds in Edge Sharing Bioctahedra.- Recent Developments in Inorganic Spectroscopy.- Exchange Effects in Polynuclear Chromium (III) Complexes.- Jahn-Teller Distortion of the 4T1 (G) State of MnCl42- in Cs3MnCl5.- Ab Initio Calculation of Electronic Transitions in Transition Metal Complexes.- The Cellular Ligand-Field Model.- The Orthonormal Operator Formulation of Symmetry-Based Ligand Fields, Rhombohedral Hierarchies as a General Example.- High and Low-Spin Interconversion in a Series of Tris (pyridylmethylamine)iron(II) Complexes.- Tetracyanobiimidazole: a Polyploid of Distinction.- The Intensities of Vibronic Origins in Transition Metal Complex Ions.- II. Reaction Rates.- Photon Echoes in Multilevel Systems.- Solvent Dynamical and Symmetrized Potential Aspects of Electron Transfer Rates.- A Theoretical Approach to Chemical Reactions at Solid Surfaces.- Electron Beams in Surface Analysis.- III. Spectroscopy.- The Spectral Properties of Molecular Propellers, With Applications to Werner-Type Complexes.- Insights into Hemoglobin Dynamics from Resonance Raman Spectroscopy.- Spin Uncoupling in the 6s Rydberg States of Methyl Iodide: The Rotational Sub-Band Structure of the One- and Two-Photon Absorption.- Spectroscopy as a Probe of Intermolecular Interactions.- Solvent, Temperature, and Band Asymmetry Features of Optical Charge Transfer Transitions in Solute Molecules in Liquids and Glasses.- The Theory of Vibrational Optical Activity.- Understanding Molecular Optical Activity.- Optical Activity (CD and CPL) as a Probe of Ion Pairing and Solution Structure of Macrocycle Complexes.- Optical Properties of Large Molecules in the Frenkel ExcitonApproximation.- Two-Photon Spectroscopy of Lanthanide (III) Complexes.- Experimental Research in the Optical Laboratory of Chemical Laboratory IV, H.C. Ørsted Institute.- IV. Floppy Molecules and the Liquid State.- Molecules: Rigid/Floppy or Solid/Liquid?.- Understanding Floppy Molecules.- Stability and Conformation of Silicon-Carbon Compounds. A Case Study of SiC2, Si2C and Si3.- Water and Aqueous Solutions.- The Effect of Structure and Solvation on the Thermodynamic Parameters for the Formation of Singly and Doubly Charged Ions of Organic Compounds in Solution.- V. Computational Quantum Chemistry.- The Energies of 3-Electron Atomic Systems Calculated by Hylleraas Type Wave Functions.- Hartree-Fock Pathology and Large Molecules.- On the Relation Between Relativity and Periodic Trends Within a Triad of Transition Metals.- A Symmetric Group Approach to the Calculation of Electronic Correlation Effects in Molecules.- Transverse Susceptibility of Spin-S Ising Chains in the Presence of a Crystal Field.- Chemical Bonds and Electronic States of Transition Metal— Containing Diatomic.