For molecules containing atoms with electrons in p orbitals, energy-level diagrams become more complex. Core electrons are usually omitted from MO energy level diagrams. Discuss with your group or the class the following: (a) Why are core electrons usually omitted? For the second-row diatomics what is the lowest MO formed from valence shell orbitals? (b) Describe how molecular orbitals are formed from atomic orbitals. Would you expect them to be higher or lower in energy than o (sigma) molecular orbitals? (c) As the nuclear charge increases, the energies of all orbitals are lowered, as shown in the figure below for homonuclear diatomics. Why does this happen?

For molecules containing atoms with electrons in p orbitals, energy-level diagrams become more complex. Core electrons are usually omitted from MO energy level diagrams. Discuss with your group or the class the following: (a) Why are core electrons usually omitted? For the second-row diatomics what is the lowest MO formed from valence shell orbitals? (b) Describe how molecular orbitals are formed from atomic orbitals. Would you expect them to be higher or lower in energy than o (sigma) molecular orbitals? (c) As the nuclear charge increases, the energies of all orbitals are lowered, as shown in the figure below for homonuclear diatomics. Why does this happen?

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter4: Molecular Structure And Orbitals

Section: Chapter Questions

Problem 78E: The diatomic molecule OH exists in the gas phase. The bond length and bond energy have been measured...

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