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5: Molecular Orbitals

  • Page ID
    60547
    • Jack Simons and Jeff Nichols
    • University of Utah and Oak Ridge National Laboratory

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    Molecular orbitals possess specific topology, symmetry, and energy-level patterns.

    • 5.1: Orbital Interaction Topology
      This page explores the impact of orbital interactions and hybridization on molecular orbitals, detailing how bonding (σ, π) and antibonding (σ*, π*) interactions are influenced by energy splittings among atomic orbitals. It notes that lighter elements favor hybridization due to smaller splittings, while heavier elements exhibit reduced hybridization with larger splittings.
    • 5.2: Orbital Symmetry
      This page highlights the significance of symmetry in classifying molecular orbitals via quantum numbers in molecules such as \(NH_3\) and \(H_2O\). It explains how symmetry helps categorize molecular orbitals into bonding, nonbonding, and antibonding types, uncovering degeneracies. By employing symmetry, complex problems can be simplified, aiding analysis. Examples demonstrate that symmetry adaptations yield consistent energy results, underlining its crucial role in molecular orbital theory.
    • 5.3: Linear Molecules
      This page explores the symmetry characteristics of linear molecules as described by \(C_{\infty n}\) and \(D_{\infty h}\) groups, highlighting their constant electrostatic potential and the classification of molecular orbitals by the m quantum number.
    • 5.4: Atoms
      This page discusses atomic symmetry, highlighting that atoms possess spherical symmetry, unlike linear molecules. This symmetry allows the Hamiltonian to commute with angular momentum components. Orbitals are classified by quantum numbers \(l\) and \(m\), leading to a 2l+1-fold degeneracy.


    This page titled 5: Molecular Orbitals was last modified on Fri, 28 Apr 2023 07:39:43 GMT and is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Jack Simons and Jeff Nichols via source content that was edited to the style and standards of the LibreTexts platform.