Carbon monoxide, orbital energy diagram

Figure 2.14. The molecular orbitals of gas phase carbon monoxide, (a) Energy diagram indicating how the molecular orbitals arise from the combination of atomic orbitals of carbon (C) and oxygen (O). Conventional arrows are used to indicate the spin orientations of electrons in the occupied orbitals. Asterisks denote antibonding molecular orbitals, (b) Spatial distributions of key orbitals involved in the chemisorption of carbon monoxide. Barring indicates empty orbitals.5 (c) Electronic configurations of CO and NO in vacuum as compared to the density of states of a Pt(lll) cluster.11 Reprinted from ref. 11 with permission from Elsevier Science.

Fig. 1.16. Qualitative molecular orbital energy diagram of carbon monoxide...

Orbital correlation diagram for carbon monoxide. The carbon atomic orbital energies are on the left, and the oxygen atomic orbital energies are on the right. The molecular orbitals that form from mixing of the atomic orbitals are represented by the horizontal lines in the center at their approximate orbital energies in the CO molecule. The vertical lines indicate the orbital occupancy. 

Considering the molecular orbital diagram of carbon monoxide (Fig. 5.201 and the discussion concerning hybridization and energy (pages 225-227). predict which end of the carbon monoxide molecule will be the more basic (i.e., will donate electrons more readily and form the stronger, direct covalent bond)... 

Fig. 5.20 Energy level diagram for the molecular orbitals of carbon monoxide. Note that upon bond formation electrons occupy orbitals that are more oxygen-like than carbon-like. Note carefully the bond order The Icr and la MOs are essentially nonbonding. The bond order, as in the N2 molecule is three.

Fig. 9.1 The (valence) molecular orbitals of ethenedione. For the correlations with the MOs of carbon monoxide only one set of CO orbitals is shown thus for example MO 1 actually results from [0(2s)+C(2s)] + [0(2s)+C(2s)], and M02 results from [0(2s)+C(2s)] - [0(2s)+C(2s)]. These AMI MO energies are very approximate. For the construction of such MO diagrams see [55] Unlike the case of 2 CO, bringing two CH2 groups together does not lead to a triplet because CHj lacks degenerate orbitals and thus so does ethene [55]...

In carbon monoxide (CO), which is isoelectronic with N2, the energies of the 2s and 2p orbitals on both C and O are close enough that they mix in a manner similar to diagram for CO. The place-... 

The MO energy diagram for Cr(CO)6 is shown in Figure 14. For the molecular orbitals, 12 electrons are contributed from the lone pairs on the carbon atoms of the six-carbon monoxide ligands. The metal contributes six electrons, while 24 electrons come from the ir-system of the six ligands. The MOs are occupied by these 42 electrons, and the t2g level becomes the HOMO of the metal carbonyl. 

The chemistry of carbon monoxide is, however, more often rationalised on a qualitative molecular orbital (MO) basis rather than in terms of its valence bond description. Figure 2.1 depicts the energy level MO diagram for carbon monoxide with occupied orbital energies determined by photoelectron spectroscopy. An approximate correlation can be made between valence bond and MO descriptions through assignment of the filled orbitals 4o and 5o to lone pairs on oxygen and carbon respectively and orbitals 3a and... 

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