Molecular single-ion magnets based on lanthanides and actinides: Design considerations and new advances in the context of quantum technologies

TLDR: In this paper, the authors review the current state of the field of lanthanide and actinide single-ion magnetism and highlight new trends in single molecule magnetism, including using f -SIMs as potential spin qubits.

About: This article is published in Coordination Chemistry Reviews.The article was published on 2017-09-01 and is currently open access. It has received 258 citations till now. The article focuses on the topics: Quantum technology.

Figures

Fig. 3. Molecular structures of selected Dy pentagonal bipyramidal complexes: (a) [[DyIII(OPCy3)2(H2O)5]3+ (9); (b) [DyIII(bbpen)Br] (10) 34]. (c) [DyIII(OPtBu(NHiPr2)2)2(H2O)5]3+ (11); (d) [DyIII(OtBu)2(py)5]+ (12) along with the out-of-phase component 𝜒′′of the ac magnetic susceptibility data plotted versus temperature for each compound. Reprinted with corresponding permissions from [33] and [34] - Copyright 2016 American Chemical Society [35] – Published by The Royal Society of Chemistry [36] – Reproduced with permission from John Wiley and Sons.

Fig. 2. (a) Molecular structure of [DyIII(BIPM)2][K(18C6)(THF)2] (8); (b) Calculated magnetic relaxation barrier for 8, where the x-axis shows the magnetic moment of each state along the C=Dy=C axis; Reprinted with permission from [32]. Published by The Royal Society of Chemistry.

Fig. 9. Crystal structure representation, perspective along the coordination z-axis showing the square-antiprismatic coordination of the central Ln ion and the φ twist angle, and energy level diagrams of the state multiplets of a) [LnPc2]- and b) [Ln(W5O18)2]9−. (a) Reprinted with permission from [41]. Copyright 2004 American Chemical Society. (b) Reprinted with permission from [90]. Copyright 2009 American Chemical Society.

Table 4.

Fig. 20. (a) Molecular structure of [YbIII(trensal)] (88); (b) Left: Rabi oscillations at selected field positions (𝐵0⊥ 𝐶3), 5 K and microwave attenuation 3 dB; Right: Corresponding Fourier transforms; (c) EDFS spectra of oriented single crystal (𝐵0||𝐶3 – blue; 𝐵0⊥𝐶3 – red) of 88 at 9.6 GHz and 5 K. Reprinted with permission from [56]. Copyright 2016 American Chemical Society.

Fig. 4. A structural correlation of axiality and coordination environment of the compounds 8-12 in respect to their magnetic behaviour: exact bond lengths, E-Dy-E bond angles of the charged donor atoms along the local pseudo-C4 or C5 of the molecules (in bold) and mean bond lengths of donor atoms along the equatorial plane or above it in the case of 8 (in italics). Adapted with corresponding permissions from refs. [32] and [35] –published by Royal Society of Chemistry; [33] and [34] – Copyright 2016 American Chemical Society; [36] - John Wiley and Sons.

Frequently asked questions

Q1. What contributions have the authors mentioned in the paper "Molecular single-ion magnets based on lanthanides and actinides" ?

Over the past fifteen years or so, the study of f-element single-ion magnets ( f-SIMs ) has gone from being a sub-discipline of molecular magnetism to an established field of research in its own right. Here, the authors review the current state of the field of lanthanide and actinide f-SIMs ; discuss the principal factors affecting the magnetic and quantum properties of such single-ion magnets ; review the latest chemical approaches in designing f-SIMs with superior properties ; and highlight new trends in single molecule magnetism, including using f-SIMs as potential spin qubits for quantum computers. 

Q2. What future works have the authors mentioned in the paper "Molecular single-ion magnets based on lanthanides and actinides" ?

Applications such as these are likely to play a leading role in the future development of fSIMs given their unrivalled potential for tunability and paradigms of robustness. Actinide f-SIMs have been comparatively less well studied, but are starting to gain momentum among various groups due to their unusual electronic properties and increased tendency to form covalent interactions, which may lead to more exotic behaviours than can be achieved with lanthanides. 

Q3. What is the goal of the majority of studies?

Although the goal of the majority of studies was the maximisation of the energy barrier Ueff (Fig. 25), as a means to increase the magnetisation blocking temperature, greater control of electronic structure has led to the application of fSIMs in a broader range of topics within spintronics [165], and in particular within the field of quantum information processing [166] (Fig. 24). 

Q4. What are the main characteristics of fSIMs?

Applications such as these are likely to play a leading role in the future development of fSIMs given their unrivalled potential for tunability and paradigms of robustness. 

Q5. What are the main reasons for the growth of fSIMs?

Actinide f-SIMs have been comparatively less well studied, but are starting to gain momentum among various groups due to their unusual electronic properties and increased tendency to form covalent interactions, which may lead to more exotic behaviours than can be achieved with lanthanides.