AI Article Synopsis
- A new theoretical framework is introduced to calculate the electronic and molecular structures of octahedrally-coordinated high-spin d(4) complexes.
- The method involves creating a (3)T1 + (5)E (O) Hamiltonian based on ligand-field matrices with trigonal symmetry, using the angular-overlap model for parameterization.
- This model simplifies the analysis by eliminating the need for temperature-dependent bonding parameters found in traditional ligand-field theory, proving effective across various vibronic-coupling strengths through specific examples.
Article Abstract
A new theoretical approach for the calculation of the electronic and molecular structures of octahedrally-coordinated high-spin d(4) complexes is described. A prescription for the construction of an effective (3)T1 + (5)E (O) Hamiltonian from the ligand-field matrices of a complex with general trigonal symmetry is given, where the ligand field is parametrized in terms of the angular-overlap model (AOM). The Jahn-Teller matrices for the (3)T1 + ((5)E⊗e) vibronic Hamiltonian are constructed and the lowest eigenvalues are calculated by a numerical method. The model obviates the need to assume a temperature dependence of bonding parameters, inherent to the conventional ligand-field-theory approach and is applicable over the whole range of vibronic-coupling strengths, as demonstrated by example calculations on the [Mn(OD2)6](3+) cation and MgO:Cr(2+).
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