Electronic structures of coordination compounds

Gas phase U. V. photoelectron spectroscopy as a tool for the investigation of electronic structures of coordination compounds. C. Cauletti and C. Farlani, Comments Inorg. Chem., 1985, 5, 29 (95). 

CNR Laboratory of Theory and Electronic Structure of Coordination Compounds, Rome. 

There are further possible advantages from the use of P.E. spectroscopy in the elucidation of the electronic structure of coordination compounds, and information not otherwise available or only indirectly available may thus come to light. The energy position of ionization bands of nonbonding orbitals, such as 6 s2 in (T1(I),... 

CHARACTERISTIC FEATURES OF THE ELECTRONIC STRUCTURE OF COORDINATION COMPOUNDS... 

To give more breadth to our discussion of the connections between molecules and solids we now consider examples of systems in which one can see transition-metal complexes. They are of pedagogical interest because their simple electronic structures can be used to good effect in elementary treatments of the electronic structure of coordination compounds. 

Until now we considered the topology of various organic molecules. In inorganic chemistry the topological methods are not so popular. Therefore, in this chapter we shall confine ourselves to only two topics, the topological theory of borane structure and the discussion of the interrelationship between topology, symmetry, and electronic structure of coordination compounds. 

Scientists have long recognized that many of the magnetic properties and colors of transition-metal complexes are related to the presence of d electrons in the metal cation. In this section we consider a model for bonding in transition-metal complexes, crystal-field theory, that accounts for many of the observed properties of these substances. Because the predictions of crystal-field theory are essentially the same as those obtained with more advanced molecular-orbital theories, crystal-field theory is an excellent place to start in considering the electronic structure of coordination compounds. 

Coordination Organometalhc Chemistry Principles Electronic Structure of Main-group Compounds Electronic Structure of OrganometaUic Compounds Electronic Structure of Clusters Ligand Field Theory Spectra Molecular Orbital Theory Symmetry Point Groups. 

Carbene Complexes Carbonyl Complexes ofthe Transition Metals Cyanide Complexes of the Transition Metals Dinuclear Organometallic Cluster Complexes Electron Transfer in Coordination Compounds Electron Transfer Reactions Theory Electronic Structure of Organometallic Compounds Luminescence Nucleic Acid-Metal Ion Interactions Photochemistry of Transition Metal Complexes Photochemistry of Transition Metal Complexes Theory Polynuclear Organometallic Cluster Complexes. 

The structures of coordination compounds are governed largely by the coordination number of the metal. Many have structures similar to the simple molecules and ions we studied in Chapter 8. Unshared pairs of electrons in d orbitals usually have only small influences on geometry because they are not in the outer shell. Table 25-7 summarizes the geometries for common coordination numbers. 

Methods for computing the geometric and electronic structures of metal compounds are advancing rapidly on all fronts. While there is a long way to go before Transition Metal computational chemistry can be described as truly predictive, techniques now exist for computing the structures and reactivities of coordination and organometallic systems to useful accuracy. As such, theory can play a powerful complementary role alongside other physical measurements. 

Comba, P. The relation between ligand structure, coordination stereochemistry and electronic and thermodynamic properties. Coord. Chem. Rev. 1993,123, 1. Comba, P. Solution structures of coordination compounds. Comments. Inorg. Chem. 1994, 16, 133. 

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