Authors:	Dorn, Matthias Hunger, David Förster, Christoph Naumann, Robert van Slageren, Joris Heinze, Katja
Title:	Towards luminescent vanadium(II) complexes with slow magnetic relaxation and quantum coherence
Online publication date:	7-Mar-2024
Year of first publication:	2022
Language:	english
Abstract:	Molecular entities with doublet or triplet ground states find increasing interest as potential molecular quantum bits (qubits). Complexes with higher multiplicity might even function as qudits and serve to encode further quantum bits. Vanadium(II) ions in octahedral ligand fields with quartet ground states and small zero-field splittings qualify as qubits with optical read out thanks to potentially luminescent spin-flip states. We identified two V2+ complexes [V(ddpd)2]2+ with the strong field ligand N,N’-dimethyl-N,N’-dipyridine-2-yl-pyridine-2,6-diamine (ddpd) in two isomeric forms (cis-fac and mer) as suitable candidates. The energy gaps between the two lowest Kramers doublets amount to 0.2 and 0.5 cm−1 allowing pulsed EPR experiments at conventional Q-band frequencies (35 GHz). Both isomers possess spin-lattice relaxation times T1 of around 300 μs and a phase memory time TM of around 1 μs at 5 K. Furthermore, the mer isomer displays slow magnetic relaxation in an applied field of 400 mT. While the vanadium(III) complexes [V(ddpd)2]3+ are emissive in the near-IR-II region, the [V(ddpd)2]2+ complexes are non-luminescent due to metal-to-ligand charge transfer admixture to the spin-flip states.
DDC:	540 Chemie 540 Chemistry and allied sciences
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 09 Chemie, Pharmazie u. Geowissensch.
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-10164
Version:	Published version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	CC BY-NC
Information on rights of use:	https://creativecommons.org/licenses/by-nc/4.0/
Journal:	Chemistry : a European journal 29 9
Pages or article number:	e202202898
Publisher:	Wiley
Publisher place:	Weinheim
Issue date:	2022
ISSN:	1521-3765
Publisher DOI:	10.1002/chem.202202898
Appears in collections:	DFG-491381577-H