For a long time, the properties of transition metal and rare earth compounds have fascinated chemists and physicists from a scientific view-point, and more recently also their enormous potential as new materials has been explored. Applications in different fields have already been realized or are under c- rent investigation, for example, new laser materials, IR to visible upconversion systems, compounds for photolithographic processes, systems involving pho- redox processes for solar energy conversion, new photovoltaic devices, chemical sensors, biosensors, electroluminescent devices (OLEDs) for flat panel display systems, supramolecular devices with wide-range definable photophysical properties, materials for energy harvesting, optical information and storage systems, etc. Metal complexes are also highly important in biology and me- cine. Most of the applications mentioned are directly related to the properties of the electronic ground state and the lower-lying excited states. Metal complexes with organic ligands or organometallic compounds exhibit outstanding features as compared to purely organic molecules. For instance, metal compounds can often be prepared and applied in different oxidation states. Furthermore, various types of low-lying electronic excitations can be induced by a suitable choice of ligands, for example, such as metal-centered transitions (MC, e. g. d-d* tran- tion), ligand-centered (LC, e. g. n-n*), metal-to-ligand-charge transfer (MLCT, e. g. d-7r*), intra-ligand-charge-transfer (ILCT) transitions, etc. In particular, the orbitals involved in the resulting lowest excited states determine the photoph- ical and photochemical properties and thus the specific use of the compoun

There exists a large literature on the spectroscopic properties of copper(II) com- 9 pounds. This is due to the simplicity of the d electron configuration, the wide variety of stereochemistries that copper(II) compounds can adopt, and the f- xional geometric behavior that they sometimes exhibit [1]. The electronic and geometric properties of a molecule are inexorably linked and this is especially true with six-coordinate copper(II) compounds which are subject to a Jahn-T- ler effect.However,the spectral-structural correlations that are sometimes d- wn must often be viewed with caution as the information contained in a typical solution UV-Vis absorption spectrum of a copper(II) compound is limited. Meaningful spectral-structural correlations can be obtained in a related series of compounds where detailed spectroscopic data is available. In the fol- 4- lowing sections two such series are examined; the six-coordinate CuF and 6 2+ Cu(H O) ions doped as impurities in single crystal hosts.Using low tempera- 2 6 ture polarized optical spectroscopy and electron paramagnetic resonance, a very detailed picture can be drawn about the geometry of these ions in both their ground and excited electronic states. We then compare the spectrosco- cally determined structural data with that obtained from X-ray diffraction or EXAFS measurements.

The unique properties and applications of transition metal compounds have long fascinated both physicists and chemists. This volume presents theoretical and experimental studies for a deeper understanding of the electronic and vibronic properties of these compounds. In particular, an introduction into properties of spin sublevels of dd*, dA*, and AA* states is given, and a modern ligand field theory based on the Angular Overlap Model is presented. In experimental case studies it is shown how to characterize different types of electronic transitions using modern methods of laser spectroscopy. Consequences of spin-orbit coupling, zero-field splittings, spin-lattice relaxations, chromophore-matrix interactions, Herzberg-Teller/Franck-Condon activities, and localization/delocalization properties are treated.

Contents G. Blasse, "Vibrational Structure in the" "Luminescence Spectra of Ions in Solids."-
A. Ceulemans, "The Doublet States in Chromium(III) Complexes." "A Shell-Theoretic View."-
H.-H. Schmidtke, "Vibrational Progressions in Electronic" "Spectra of Complex Compounds Indicating Strong Vibronic" "Coupling."-
P.E. Hoggard, "Sharp-Line Electronic Spectra and Metal-Ligand" "Geometry."- M. Colombo, A. Hauser, H.U. Gudel, "Competition" "Between Ligand Centered and Charge Transfer Lowest Excited" "States in bis Cyclometalated Rh3+ and Ir3+ Complexes."- D. Wexler, J.I. Zink, C. Reber, "Spectroscopic Manifestations of" "Potential" "Surface Coupling Along Normal Coordinates in " "Transition" " Metal Complexes.""

For a long time, the properties of transition metal and rare earth compounds have fascinated chemists and physicists from a scientific view-point, and more recently also their enormous potential as new materials has been explored. Applications in different fields have already been realized or are under c- rent investigation, for example, new laser materials, IR to visible upconversion systems, compounds for photolithographic processes, systems involving pho- redox processes for solar energy conversion, new photovoltaic devices, chemical sensors, biosensors, electroluminescent devices (OLEDs) for flat panel display systems, supramolecular devices with wide-range definable photophysical properties, materials for energy harvesting, optical information and storage systems, etc. Metal complexes are also highly important in biology and me- cine. Most of the applications mentioned are directly related to the properties of the electronic ground state and the lower-lying excited states. Metal complexes with organic ligands or organometallic compounds exhibit outstanding features as compared to purely organic molecules. For instance, metal compounds can often be prepared and applied in different oxidation states. Furthermore, various types of low-lying electronic excitations can be induced by a suitable choice of ligands, for example, such as metal-centered transitions (MC, e. g. d-d* tran- tion), ligand-centered (LC, e. g. n-n*), metal-to-ligand-charge transfer (MLCT, e. g. d-7r*), intra-ligand-charge-transfer (ILCT) transitions, etc. In particular, the orbitals involved in the resulting lowest excited states determine the photoph- ical and photochemical properties and thus the specific use of the compoun

There exists a large literature on the spectroscopic properties of copper(II) com- 9 pounds. This is due to the simplicity of the d electron configuration, the wide variety of stereochemistries that copper(II) compounds can adopt, and the f- xional geometric behavior that they sometimes exhibit [1]. The electronic and geometric properties of a molecule are inexorably linked and this is especially true with six-coordinate copper(II) compounds which are subject to a Jahn-T- ler effect.However,the spectral-structural correlations that are sometimes d- wn must often be viewed with caution as the information contained in a typical solution UV-Vis absorption spectrum of a copper(II) compound is limited. Meaningful spectral-structural correlations can be obtained in a related series of compounds where detailed spectroscopic data is available. In the fol- 4- lowing sections two such series are examined; the six-coordinate CuF and 6 2+ Cu(H O) ions doped as impurities in single crystal hosts.Using low tempera- 2 6 ture polarized optical spectroscopy and electron paramagnetic resonance, a very detailed picture can be drawn about the geometry of these ions in both their ground and excited electronic states. We then compare the spectrosco- cally determined structural data with that obtained from X-ray diffraction or EXAFS measurements.

The unique properties and applications of transition metal compounds have long fascinated both physicists and chemists. This volume presents theoretical and experimental studies for a deeper understanding of the electronic and vibronic properties of these compounds. In particular, an introduction into properties of spin sublevels of dd*, dA*, and AA* states is given, and a modern ligand field theory based on the Angular Overlap Model is presented. In experimental case studies it is shown how to characterize different types of electronic transitions using modern methods of laser spectroscopy. Consequences of spin-orbit coupling, zero-field splittings, spin-lattice relaxations, chromophore-matrix interactions, Herzberg-Teller/Franck-Condon activities, and localization/delocalization properties are treated.

The "Seventh International Symposium on the Photochemistry and Photo- physics of Coordination Compounds" was held in the charming Schlo~ Elmau lying in a hidden valley of the Bavarian Alps above Garmisch- Partenkirchen, Federal Republic of Germany, from March 29 to April 2, 1987. About ninety participants from seventeen countries including about thirty non-European scientists as far away as Japan and Australia came together for this symposium. Forty-five oral and twenty-five poster contributions were presented. These presentations and the opportunity for many formal and informal discussions stimulated an intense scienti- fic interaction between the participants. This meeting followed previous symposia held in Muhlheim 1974 (Koerner von Gustorf), Ferrara 1976 (Carassiti, Scandola), Koln 1978 (Wasgestian), Montreal 1980 (Serpone), Paris 1982 (Gianotti) and London 1984 (Harriman). The main fields covered by this 7th Symposium were photo-redox processes, organometallic photochemistry, and properties of metal centered excited states. Furthermore, special complexes such as 2+ [Ru(bpy)3] and related compounds as well as Cr(III)-complexes were discussed extensively. Moreover, a series of potential applications such as solar energy conversion and storage (e.g. water splitting) and photoresist technology were important subjects of this meeting. Thus, it was shown again that the rapidly expanding field of excited-state chemistry and physics of coordination compounds has become an important part of inorganic chemistry.

This brand-new monograph on organic light emitting diodes, edited by a pioneer, and written by front-line researchers from academia and industry, provides access to the latest findings in this rapidly growing field. More than ten contributions cover all areas -- from theory and basic principles, to different emitter materials and applications in production.