A Flexible Iron(ii) Complex in Which Zero-Field Splitting is Resistant to Structural Variation
Journal Article - Open Access
NORTHWESTERN UNIV EVANSTON IL EVANSTON United States
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The relationship between electronic structure and zero-field splitting dictates key design parameters for magnetic molecules. In particular, to enable the directed synthesis of new electronic spin based qubits, developing complexes where zero-field splitting energies are invariant to structural changes is a critical challenge. Toward those ends, we report three salts of a new compound, a four-coordinate ironII complex FeC3S522 18-crown-6K 1, Ph4P 2, Bu4N 3 with a continuous structural variation in a single parameter, the dihedral angle d between the two C3S52 ligands, as a function of counter ion d 89.984 for 1 to 72.412 for 3. Electron paramagnetic resonance data for 13 reveal zero-field splitting parameters that are unusually robust to the structural variation. Mssbauer spectroscopic measurements indicate that the structural variation in d primarily affects the highest-energy 3d-orbitals dxz and dyz of the ironII ion. These orbitals have the smallest impact on the zero-field splitting parameters, thus the distortion has a minor effect on D and E. These results represent the first part of a directed effort to understand how spin state energies may be fortified against structural distortions for future applications of qubits in non-crystalline environments.
- Electricity and Magnetism