Record Quantum Tunneling Time in an Air-Stable Exchange-Bias Dysprosium Macrocycle

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(28), С. 18899 - 18904

Опубликована: Июль 8, 2024

In recent years, dysprosium macrocycle single-molecule magnets (SMMs) have received increasing attention due to their excellent air/thermal stability, strong magnetic anisotropy, and rigid molecular skeleton. However, they usually display fast zero-field quantum tunneling of the magnetization (QTM) rate, severely hindering data storage applications. Herein, we report design, synthesis, characterization an air-stable monodecker didysprosium integrating single-ion near-perfect local crystal field (CF) symmetry, efficient exchange bias. These indispensable features enable clear-cut elucidation crucial role very weak antiferromagnetic coupling on dynamics, creating a prominent SMM with large effective energy barrier (

Язык: Английский

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Diatomic C₂/NC Ligand Induced Conformation Variation of Trimetallic Clusters within a Carbon Cage

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Фев. 27, 2025

Understanding the interplay between conformation and electronic properties of metal complexes at atomic level is key for rational design new functional molecules. Trimetallic clusterfullerenes (TMCFs) encapsulating quinary M3C2 carbide or M3NC carbonitride clusters offer an ideal model system elucidating conformation-electronic property correlation due to its unusual conformational versatility. Herein, we synthesize isolate two novel lanthanide-transition heteronuclear TMCFs, namely, CeTi2C2@Ih(7)-C80 CeTi2NC@Ih(7)-C80. Crystallographic studies reveal singly bonded C2/NC ligands coordinating vertically CeTi2 trimetallic plane within cluster, drastically different from bat-ray conformations reported all homonuclear TMCFs. Such bonding characters give rise variable structures [Ce4+(Ti2)8+(C2)6–]6+@C806– [Ce3+(Ti2)8+(NC)5–]6+@C806–, featuring a fixed tetravalent oxidation state Ti tunable states Ce (Ce4+/Ce3+), as confirmed by X-ray absorption spectroscopy magnetic measurements in combination with theoretical studies. Furthermore, scrutinizing TMCFs bearing M3C2/M3NC clusters, find that carbide/carbonitride are precisely dictated nature diatomic ligand so suffice strong coordination interactions encapsulated metals. Following such general rule governing variation, very field achieved on Ce3+ presence NC CeTi2NC@C80, giving first Ce-based single-molecule magnet shows open hysteresis 2 K.

Язык: Английский

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Thirty Years of Hide-and-Seek: Capturing Abundant but Elusive M^III@C_3v(8)-C₈₂ Isomer, and the Study of Magnetic Anisotropy Induced in Dy³⁺ Ion by the Fullerene π-Ligand

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(36), С. 25328 - 25342

Опубликована: Сен. 2, 2024

Our knowledge about endohedral metallofullerenes (EMFs) is restricted to the structures with sufficient kinetic stability be extracted from arc-discharge soot and processed by chromatographic structural techniques. For most abundant rare-earth monometallofullerene M

Язык: Английский

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Recent advances of dinuclear dysprosium-based single-molecule magnets: from mechanisms to application

Journal of Materials Chemistry C, Год журнала: 2024, Номер 12(37), С. 14754 - 14773

Опубликована: Янв. 1, 2024

This review focused on the research of Dy 2 -SMMs for years and took advantage intricate relaxation mechanisms, manipulating strategies synthesizing high-performance to provide insights design -SMMs.

Язык: Английский

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Anomalous Magnetic Hysteresis up to 20 K in a Non‐Kramers Light‐Lanthanide Single‐Molecule Magnet

Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

Abstract Light‐lanthanides (Ln), despite their widespread uses in commercial permanent magnets, are among the least explored metal elements as building blocks of single‐molecule magnets (SMMs) due to smaller magnetic moments well weaker spin–orbit couplings than those heavy‐Ln counterparts, and so far, only a neodymium (Nd) complex has been reported showing small hysteresis at 2 K. Here, we report low‐coordination praseodymium (Pr) complex, namely, Pr@C 81 N, featuring non‐Kramers trivalent Pr ion entrapped within an azafullerene cage behaving first Pr‐based SMM. Although weak nonaxial ligand field imposed by carbon on integer‐spin Pr(III) elicits nondegenerate spin states, N shows anomalous up 20 K using sweep rate Oe/s, which is highest temperature all light‐Ln SMMs. In addition ideally minimized spin–phonon coupling low coordination, origin such unexpected bistability for likely lies nuclear sublevels arising from large hyperfine coupling, feature distinct electronic magnetizations highly mixed ground state.

Язык: Английский

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Anomalous Magnetic Hysteresis up to 20 K in a Non‐Kramers Light‐Lanthanide Single‐Molecule Magnet

Angewandte Chemie, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

Abstract Light‐lanthanides (Ln), despite their widespread uses in commercial permanent magnets, are among the least explored metal elements as building blocks of single‐molecule magnets (SMMs) due to smaller magnetic moments well weaker spin–orbit couplings than those heavy‐Ln counterparts, and so far, only a neodymium (Nd) complex has been reported showing small hysteresis at 2 K. Here, we report low‐coordination praseodymium (Pr) complex, namely, Pr@C 81 N, featuring non‐Kramers trivalent Pr ion entrapped within an azafullerene cage behaving first Pr‐based SMM. Although weak nonaxial ligand field imposed by carbon on integer‐spin Pr(III) elicits nondegenerate spin states, N shows anomalous up 20 K using sweep rate Oe/s, which is highest temperature all light‐Ln SMMs. In addition ideally minimized spin–phonon coupling low coordination, origin such unexpected bistability for likely lies nuclear sublevels arising from large hyperfine coupling, feature distinct electronic magnetizations highly mixed ground state.

Язык: Английский

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Lanthanide–nickel molecular intermetallic complexes featuring a ligand-free Ni2− anion in endohedral fullerenes

Nature Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 23, 2025

Язык: Английский

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Molecular spin relaxation of f-block metal complexes for quantum applications in a nutshell (Review article)

Low Temperature Physics, Год журнала: 2025, Номер 51(5), С. 517 - 532

Опубликована: Май 1, 2025

This is a critical report on the most recent progress towards implementation of single-ion/molecule magnets (SIM/SMMs) in molecular spin qubits. Short flash-back to effect lattice distortions doubly degenerate state manganites, mirrored by magnetic bistability SMMs, followed summary suppression quantum decoherence SIM/SMMs units slowing spin-lattice relaxation and avoiding level crossings.

Язык: Английский

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A Linear Dysprosium(II) Metallocene with a High Effective Energy Barrier and Magnetic Hysteresis up to 70 Kelvin

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Май 14, 2025

Dysprosium in the oxidation state +3 is ubiquitous studies of single-molecule magnets (SMMs). In contrast, SMMs based on lanthanides +2 are rare, and examples with both a high effective energy barrier to reversal magnetization hysteresis coercivity at temperatures extremely uncommon. Here, we show that one-electron reduction dysprosium(III) complex [(η5-C5iPr5)Dy(η5-Cp*)(BH4)] (Cp* = C5Me5) KC8 generates linear dysprosium(II) metallocene [(η5-C5iPr5)Dy(η5-Cp*)]. Magnetic measurements, ultraviolet/visible/near infrared (UV/vis/NIR) spectroscopy theoretical calculations center [(η5-C5iPr5)Dy(η5-Cp*)] adopts 4f9 (6s/5d)1 configuration. Coupling 4f 5d electrons results an magnetic moment 11.38 μB 217 K, equaling highest recorded for mononuclear complex. AC DC measurements establish SMM properties [(η5-C5iPr5)Dy(η5-Cp*)], including 1551 cm-1, largest yet reported divalent lanthanide SMM, 100-s blocking temperature 62 K. produce loops remain open up 70 Multireference reveal easy-axis ground doublet coincides molecular symmetry axis, this has strong axial character. The axiality Orbach relaxation probably occurring via second-excited doublet. parameters insight suggest linked perfectly crystal field experienced by center.

Язык: Английский

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Ti3C3@C2v(9)-C82: a double-butterfly tri-metal carbide cluster inside a fullerene cage

Chemical Communications, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

An unprecedented double-butterfly Ti 3 C cluster with a rare Ti–C coordination mode was stabilized inside 82 cage, forming novel tri-metal carbide clusterfullerene, @ 2 v (9)-C .

Язык: Английский

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