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The rise of quantum information science has spurred chemists to prepare new molecules that serve as useful building blocks in quantum technologies of the future. Implementation of molecular spin-based qubits requires new methods to induce high spin polarization of samples. Herein, we report design criteria to develop axially symmetric spin-1/2 molecules amenable to optically induced magnetization (OIM), a technique using circularly polarized (CP) excitation to deliver spin polarization. We apply these criteria to develop a series of tungsten(V) chalcogenide complexes that are demonstrated to have large spin-sensitive responses to CP light using magnetic circular dichroism (MCD) that could allow up to ∼20% spin polarization through OIM. Pulsed electron paramagnetic resonance (EPR) spectra reveal these systems have improved relaxation times over molecules like K2IrCl6, a species recently investigated by OIM, and field-swept electron spin−echo (FS-ESE) experiments show they have a remarkable lack of anisotropy in their phase-memory Tm times. The design criteria are general and point toward future ways to improve OIMinitializable qubits.
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Pulsed EPR Signals from Triplets
Abstract Pulsed EPR experiments have proven to be an important tool for measuring EPR spectra, kinetics and relaxation rates of free radicals and triplet molecules. The EPR frequencies and selection rules from CW-EPR spectra also govern pulsed EPR-experiments, but pulsed excitation provides much greater control over spin dynamics and allows clean separation and measurement of many properties of the spin system. Most pulsed EPR measurements of triplet molecules have been made in the selective pulse limit where only one EPR transition of a molecule is excited by microwave pulses and its EPR spectroscopy behaves like that of a radical with spin of
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- Award ID(s):
- 1416238
- PAR ID:
- 10025952
- Date Published:
- Journal Name:
- Zeitschrift für Physikalische Chemie
- Volume:
- 231
- Issue:
- 3
- ISSN:
- 0942-9352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/zpch-2016-0869
