Degenerate orbitals molecular

In the case of the cyclopentadienyl cation, there are only two electrons in the e" tt molecular orbitals that are degenerate in Dji, symmetry. The MO heatments... 

That no degenerate molecular orbitals arose in the above examples is a result of the fact that the C2v point group to which H2O and the allyl system belong (and certainly the... 

Asimple example is the formation of the hydrogen molecule from two hydrogen atoms. Here the original atomic energy levels are degenerate (they have equal energy), but as the two atoms approach each other, they interact to form two non degenerate molecular orbitals, the lowest of which is doubly occupied. 

Figure 7.14 Molecular orbital energy level diagram for first-row homonuclear diatomic molecules. The 2p, 2py, 2p atomic orbitals are degenerate in an atom and have been separated for convenience. (In O2 and F2 the order of

Figure 15.3 The six benzene tt molecular orbitals. The bonding orbitals >p2 and t 3 have the same energy and are said to be degenerate, as are the antibonding orbitals tf/4 and 5. The orbitals and 4 have no tt electron density on two carbons because of a node passing through these atoms.

Figure 15.10 Energy levels of the six benzene 77 molecular orbitals. There is a single, lowest-energy orbital, above which the orbitals come in degenerate pairs.

The relevant orbitals to consider are the molecular orbitals 5Aj and 6A, of cyclopropene (III.46) which correlate with the lowest acc orbital of cyclopropane (3A, III.56) and with one of the higher degenerate <7CC orbitals (3E, III.56). The cyclopropene orbitals are very similar to their cyclopropane counterparts. In particular the 6Aj orbital is a linear combination of all three crcc bond orbitals and extends over the entire cyclopropene molecule. Its amplitude, shown in Fig. 46, is fairly accurately represented by the... 

In methyl fluoride the three lone-pair molecular orbitals divide into two degenerate, purely p-type orbitals and a deeper cr-type orbital (III.33J (see Fig. 48). The p-type orbitals on fluorine can be labeled "eclipsed and bisected , by analogy with the eon-... 

Figure 3. Molecular-orbital diagrams as obtained by the ROHF method. Dashed lines indicate MOs dominated by the metal d-orbitals, the solid lines stand for doubly occupied or virtual ligand orbitals. Orbitals which are close in energy are presented as degenerate the average deviation from degeneracy is approximately 0.01 a.u. In the case of a septet state (S=3), the singly occupied open-shell orbitals come from a separate Fock operator and their orbital energies do not relate to ionization potentials as do the doubly occupied MOs (i.e. Koopmann s approximation). For these reasons, the open-shell orbitals appear well below the doubly occupied metal orbitals. Doubly occupying these gives rise to excited states, see text.

Fig. 1 A schematic illustration of the in-phase and out-of-phase combinations of the atomic orbitals into the bonding and antibonding molecular orbitals, respectively. The dissociation limit of a H molecule corresponds to a pure diradical with degenerate singlet and triplet states...

Molecules with two or more unpaired electrons may be divided into two classes by far the most common examples are molecules where the unpaired electrons are contained in a set of degenerate atomic or molecular orbitals with qualitatively similar spatial distributions, e.g., an octahedral Cr(m) (4A2g) or Ni(n) (3A2g) complex, a ground state triplet molecule like 02, or the excited triplet states of naphthalene or benzophenone. 

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