TY - JOUR
T1 - Ligand Effects on the Spin Relaxation Dynamics and Coherent Manipulation of Organometallic La(II) Potential Qu d its
AU - Nodaraki, Lydia E.
AU - Ariciu, Ana-Maria
AU - Huh, Daniel N.
AU - Liu, Jingjing
AU - Martins, Daniel O. T. A.
AU - Ortu, Fabrizio
AU - Winpenny, Richard E. P.
AU - Chilton, Nicholas F.
AU - McInnes, Eric J. L.
AU - Mills, David P.
AU - Evans, William J.
AU - Tuna, Floriana
N1 - Publisher Copyright:
© 2024 The Authors. Published by American Chemical Society.
PY - 2024/6/5
Y1 - 2024/6/5
N2 - We present pulsed electron paramagnetic resonance (EPR) studies on three La(II) complexes, [K(2.2.2-cryptand)][La(Cp′)
3] (1), [K(2.2.2-cryptand)][La(Cp″)
3] (2), and [K(2.2.2-cryptand)][La(Cp
tt)
3] (3), which feature cyclopentadienyl derivatives as ligands [Cp′ = C
5H
4SiMe
3; Cp″ = C
5H
3(SiMe
3)
2; Cp
tt = C
5H
3(CMe
3)
2] and display a C
3 symmetry. Long spin-lattice relaxation (T
1) and phase memory (T
m) times are observed for all three compounds, but with significant variation in T
1 among 1-3, with 3 being the slowest relaxing due to higher s-character of the SOMO. The dephasing times can be extended by more than an order of magnitude via dynamical decoupling experiments using a Carr-Purcell-Meiboom-Gill (CPMG) sequence, reaching 161 μs (5 K) for 3. Coherent spin manipulation is performed by the observation of Rabi quantum oscillations up to 80 K in this nuclear spin-rich environment (
1H,
13C, and
29Si). The high nuclear spin of
139La (I = 7/2), and the ability to coherently manipulate all eight hyperfine transitions, makes these molecules promising candidates for application as qudits (multilevel quantum systems featuring d quantum states; d >2) for performing quantum operations within a single molecule. Application of HYSCORE techniques allows us to quantify the electron spin density at ligand nuclei and interrogate the role of functional groups to the electron spin relaxation properties.
AB - We present pulsed electron paramagnetic resonance (EPR) studies on three La(II) complexes, [K(2.2.2-cryptand)][La(Cp′)
3] (1), [K(2.2.2-cryptand)][La(Cp″)
3] (2), and [K(2.2.2-cryptand)][La(Cp
tt)
3] (3), which feature cyclopentadienyl derivatives as ligands [Cp′ = C
5H
4SiMe
3; Cp″ = C
5H
3(SiMe
3)
2; Cp
tt = C
5H
3(CMe
3)
2] and display a C
3 symmetry. Long spin-lattice relaxation (T
1) and phase memory (T
m) times are observed for all three compounds, but with significant variation in T
1 among 1-3, with 3 being the slowest relaxing due to higher s-character of the SOMO. The dephasing times can be extended by more than an order of magnitude via dynamical decoupling experiments using a Carr-Purcell-Meiboom-Gill (CPMG) sequence, reaching 161 μs (5 K) for 3. Coherent spin manipulation is performed by the observation of Rabi quantum oscillations up to 80 K in this nuclear spin-rich environment (
1H,
13C, and
29Si). The high nuclear spin of
139La (I = 7/2), and the ability to coherently manipulate all eight hyperfine transitions, makes these molecules promising candidates for application as qudits (multilevel quantum systems featuring d quantum states; d >2) for performing quantum operations within a single molecule. Application of HYSCORE techniques allows us to quantify the electron spin density at ligand nuclei and interrogate the role of functional groups to the electron spin relaxation properties.
UR - http://www.scopus.com/inward/record.url?scp=85194185403&partnerID=8YFLogxK
U2 - 10.1021/jacs.3c12827
DO - 10.1021/jacs.3c12827
M3 - Article
SN - 0002-7863
VL - 146
SP - 15000
EP - 15009
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 22
ER -