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Electron paramagnetic resonance g-tensors from state interaction spin-orbit coupling density matrix renormalization
Elvira R Sayfutyarova1, Garnet Kin-Lic Chan2
1Department of Chemistry, Princeton University, Princeton, New Jersey 08543, USA.
The Journal of Chemical Physics
|May 17, 2018
Summary
We developed a new method to calculate electron paramagnetic resonance g-tensors using advanced computational chemistry. This technique enables accurate g-tensor predictions for complex molecules with multiple electron spins.
Area of Science:
- Computational chemistry
- Quantum mechanics
- Spectroscopy
Background:
- Electron paramagnetic resonance (EPR) spectroscopy is crucial for studying paramagnetic species.
- Accurate calculation of EPR g-tensors is challenging for systems with complex electronic structures.
- Multireference methods are often required for systems with multiple open shells.
Purpose of the Study:
- To present a novel state interaction spin-orbit coupling method for calculating EPR g-tensors.
- To validate the method using Density Matrix Renormalization Group (DMRG) wavefunctions.
- To demonstrate the method's applicability to challenging chemical systems.
Main Methods:
- State interaction spin-orbit coupling method.
- Density Matrix Renormalization Group (DMRG) wavefunction calculations.
- Application to transition metal complexes and metalloenzyme models.
Main Results:
- Successfully computed g-tensors for TiF3 and CuCl4(2-) complexes.
- Calculated g-tensors for a [2Fe-2S] ferredoxin model.
- Determined g-tensors for a Mn4CaO5 model of the oxygen evolving complex S2 state.
Conclusions:
- The developed method accurately calculates g-tensors from DMRG wavefunctions.
- This approach extends the capability of determining g-tensors in demanding multireference systems.
- The study opens avenues for EPR g-tensor analysis in complex, open-shell systems.
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