Chemical Control of Vibronic Coupling for Magnetic Materials

Projektinformationen

ContraVib

ID Finanzhilfevereinbarung: 851504

DOI

10.3030/851504

Projekt abgeschlossen

EK-Unterschriftsdatum 6 September 2019

Startdatum 1 Februar 2020

Enddatum 31 Juli 2025

Finanziert unter

• EXCELLENT SCIENCE - European Research Council (ERC)

Gesamtkosten

€ 1 945 994,00

EU-Beitrag

€ 1 945 994,00

Koordiniert durch

THE UNIVERSITY OF MANCHESTER
United Kingdom

Periodic Reporting for period 3 - ContraVib (Chemical Control of Vibronic Coupling for Magnetic Materials)

Berichtszeitraum: 2023-02-01 bis 2024-07-31

Zusammenfassung vom Kontext und den Gesamtzielen des Projekts

Vibrations in materials allow the exchange of energy between different parts. This fundamental interaction controls magnetism and electronic properties at the nanoscale, and so has important consequences in areas as diverse as data storage, magnetic resonance imaging, efficient lighting, and quantum computing. In the context of magnetism in molecules, vibrations permit switching the magnetic moment, however this occurs in materials spontaneously. Thus, if we hope to control the magnetism of molecules, for instance to make ultra-high-density data storage devices, we must control the coupling between the magnetic properties of molecules and the vibrations. The core objectives of this research programme are to develop a computational method to probe these interactions and understand how they can be controlled with chemistry.

Specifically:

1) Build a computational framework for calculation of the vibrational coupling.
1a) Establish influence of vibrational anharmonicity.
1b) Integrate delocalised vibrational modes.
1c) Investigate vibrational coupling changes in different environments.
1d) Implement ultra-high-quality calculations into the computational framework.
1e) Determine quantum dynamics of spin systems.

2) Collect experimental data to benchmark the computational framework.
2a) Measure magnetic field- and temperature-dependent magnetisation dynamics of molecules in different environments.
2b) Measure electronic and vibrational energies in different environments.
2c) Measure the quantum memory-loss pathway in molecules in different environments.

Arbeit, die ab Beginn des Projekts bis zum Ende des durch den Bericht erfassten Berichtszeitraums geleistet wurde, und die wichtigsten bis dahin erzielten Ergebnisse

We have built a team to achieve the objectives. Direct progress towards the objectives is as follows:

1)
1a) We have calculated the vibrational anharmonicity and are poised to calculate its effect very shortly. Paper A is in preparation.
1b) We have integrated delocalised vibrational modes. Paper B and C are in preparation.
1c) We have built a tool to allow calculation of vibrational coupling in different environments. Yu et al., Chem, 2020, 6, 1777; Reta et al., J. Am. Chem. Soc., 2021, 143, 5943; Kragskow et al., Nature Commun., 2022, 13, 825; paper C in preparation.
1d) We have a plan for how to implement ultra-high-quality calculations into the computational framework.
1e) We have results showing how vibrations lead to loss of quantum coherence in molecules. Paper D is in preparation.

2)
2a) We have measured magnetic field- and temperature-dependent magnetisation dynamics of molecules in different environments. Yu et al., Chem, 2020, 6, 1777; Lu et al., Inorg. Chem. Front., 2020, 7, 2941; Wang et al., Angew. Chem. Int. Ed., 2021, 60, 5299; Thomas-Hargreaves et al., Chem. Commun., 2021, 57, 733; Thomas-Hargreaves et al., Chem. Sci., 2021, 12, 3911; Ding et al., Inorg. Chem., 2022, 61, 227; Gould et al., Science, 2022, 375, 198; Gould et al., Science, 2022, 375, 198.
2b) We have used neutron scattering to measure vibrational energies, but electronic energy measurement has proven more difficult. Garlatti et al., J. Phys. Chem. Lett., 2021, 2021, 12, 8826.
2c) We have measured the quantum memory-loss pathway in molecules in three different environments. Paper E is in preparation.

Other achievements:
- Measurement of magnetic exchange coupling: Giansiracusa et al., Inorg. Chem. Front., 2020, 7, 3909
- Method to extract "hidden" relaxation data from experiments: Reta and Chilton, Chem. Sq., 2020, 4, 3
- Isolation and study of first ferrocene anion: Goodwin et al., Nature Chem., 2021, 13, 243
- Unraveling unexpected magnetism in uranium molecules: Seed et al., Chem, 2021, 7, 1666.
- Assessed accuracy of minimal computational methods: Walisinghe and Chilton, Dalton Trans., 2021, 50, 14130.
- Developed new tools to characterise best molecular magnet to-date: Gould et al., Science, 2022, 375, 198.

Fortschritte, die über den aktuellen Stand der Technik hinausgehen und voraussichtliche potenzielle Auswirkungen (einschließlich der bis dato erzielten sozioökonomischen Auswirkungen und weiter gefassten gesellschaftlichen Auswirkungen des Projekts)

1) We can accurately predict magnetic dynamics of new molecules.
2) We discovered and explained the magnetic properties of the strongest magnet yet made
3) We have made excellent progress towards all objectives.

Expected results:
a) Effect of anharmonicity expounded
b) Effects of different environmental vibrations clarified
c) Understanding how vibrations effect quantum states of molecules
d) Design strategies for weak vibrational coupling