Valence molecular orbitals formaldehyde

Fig. 17.2 The valence molecular orbitals of formaldehyde [lOSSa]. The solid and...

Formaldehyde (methanal, COH ) is an apposite starting point for a discussion of the electronic structure of the carbonyl halides, as its orbital interactions are relatively simple. Like the carbonyl halides, the ground state of COHj is planar with C2y symmetryt, and its molecular orbitals can be constructed from those of carbon monoxide and the Is atomic orbitals of two hydrogen atoms (see Fig. 17.1). Its valence electron configuration is ... 

As another example of the use of symmetry as a classifying and simplifying device in valence theory we will discuss formaldehyde. In this case we will not only consider the ir electrons but also the molecular orbitals,. and the nonbonding orbitals. The formaldehyde molecule belongs to C20 symmetry and the C—O bond direction is chosen parallel to the z axis and the molecular plane as yz. There are 12 electrons in the valence shell of formaldehyde Ha(.is), C(2s2p ), 0(2s"2p ). The... 

A diagram of the geometry and axis conventions for ketene is shown in Fig. 36. The molecule has a planar structure with symmetry. The molecular orbitals in the ketene molecule are not directly analogous to those of formaldehyde, as was recognized in early ab initio studies Ketene is a 22 electron system with 16 valence electrons. The molecular orbitals can be classified according to their behavior under the symmetry operations of the molecular point group, C, . Detailed MO calculations have established that the ground state orbital occupancy is ... 

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