Orbitals and Hybridization in Electron-Sharing Bonds of Transition Metals

Valence Orbitals and Hybridization in Electron-Sharing Bonds of Transition Metals 

It becomes obvious that the molecular shapes that are associated with sd hybridized orbitals differ strongly from sp hybrids. This is because d orbitals have more lobes than p orbitals, which makes the correlation between sd hybridization and bond angles less obvious. The theoretical bond angles, for example, between 

It is illuminating to compare the sd hybridization inTM compounds, which carry substituents with and without lone-pair orbitals, with sp hybridization in relation to main-group molecules. Table 7.1 shows the results for Me TMCl (TM = Ti, Zr, Hf) and Me2ECl2 (E = C, Si, Ge, Sn, Pb) [14]. AH main-group compounds have 

The values calculated for the (COljTM - CO o-donation consecutively increase from Hf(CO)g to lr(CO)g, whereas the (COljTMi CO Ji-backdonation decreases in the same order. This is reasonable, because the vacant d(ji) acceptor orbital of (CO)jTM becomes lower in energy when q becomes less negative or 

Metal orbitals Ligand orbitals Metal orbitals Ligand orbitals 

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