Octahedral geometry ruthenium

The second complex has been characterized by X-ray crystallography223. The ruthenium(II) atom is coordinated to three Me2SO molecules via the oxygen atom and to three via the sulphur atom to give the irregular octahedral geometry as shown in Scheme 18. 

It is, thus, important that the ruthenium(II) complexes that are to be used as building blocks of the future machines contain sterically hindering chelates so as to force the coordination sphere of the metal to be distorted from the perfect octahedral geometry. We will discuss the photochemical reactivity of rotaxanes and catenanes of this family as well as non-interlocking systems like scorpionates since the lability of bulky monodentate ligands could also lead to useful photosubstitution reactions. 

For all the above reasons, ruthenium has become a very popular redox site as a (relatively cheap) heavy metal, its complexes are kinetically stable and its crystal field A parameter value is relatively high. Hence, for most common complexes of ruthenium(II) of pseudo-octahedral geometry, the d electronic configuration is a low-spin diamagnetic state, and frontier orbitals, involved in the redox processes are essentially of the nonbonding tag type. Eventually its rich photochemistry may be used to probe excited-state behaviors. 

After the advent of the nonclassical if-Vi.2 complexes, polyhydrides had to be reinterpreted [14]. Thus, RuH4(PPh3)3 is not a classical tetrahydride of coordination number seven at the ruthenium atom but a dihydride-dihydrogen complex Ru(H2)(H)2(PPh3)3 of octahedral geometry [25]. 

Particularly, ruthenium (Ru) (II) complexes have been used extensively as CT sensitizers on nanocrystalline Ti02 films [22]. The choice of ruthenium metal is of special interest for a number of reasons (1) because of its octahedral geometry, one can introduce specific ligands in a controlled manner (2) the photophysical, photochemical, and the electrochemical... 

General Structural Features. The general structure of halfsandwich ruthenium(II)-arene complexes is shown in Fig. 12. The structural, stereochemical and electronic features of metal-arene complexes have been discussed (63). A typical piano-stool geometry consists of an rj6-arene occupying three coordination sites of the pseudo-octahedral complex, leaving the three legs X, Y, and Z available for coordination. The sites X and Y can be taken up by two monodentate ligands, but are more commonly... 

The most common oxidation states and the corresponding electronic configuration of ruthenium are +2 (d) and +3 ( ). Compounds are usually octahedral. Compounds in oxidations states from —2 (coordination geometries. Important applications of ruthenium compounds include oxidation of organic compounds and use in dimensionally stable anodes (DSA). 

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