0000000001299938
AUTHOR
Fu-sheng Guo
Rare‐earth cyclobutadienyl sandwich complexes: Synthesis, structure and dynamic magnetic properties
The potassium cyclobutadienyl [K2{η4‐C4(SiMe3)4}] (1) reacts with MCl3(THF)3.5 (M=Y, Dy) to give the first rare‐earth cyclobutadienyl complexes, that is, the complex anions [M{η4‐C4(SiMe3)4}{η4‐C4(SiMe3)3‐κ‐(CH2SiMe2}]2−, (2M), as their dipotassium salts. The tuck‐in alkyl ligand in 2M is thought to form through deprotonation of the “squarocene” complexes [M{η4‐C4(SiMe3)4}2]− by 1. Complex 2Dy is a single‐molecule magnet, but with prominent quantum tunneling. An anisotropy barrier of 323(22) cm−1 was determined for 2Dy in an applied field of 1 kOe, and magnetic hysteresis loops were observed up to 7 K. nonPeerReviewed
A Dysprosium Metallocene Single-Molecule Magnet Functioning at the Axial Limit
Abstraction of a chloride ligand from the dysprosium metallocene [(Cpttt)2DyCl] (1Dy Cpttt=1,2,4‐tri(tert‐butyl)cyclopentadienide) by the triethylsilylium cation produces the first base‐free rare‐earth metallocenium cation [(Cpttt)2Dy]+ (2Dy) as a salt of the non‐coordinating [B(C6F5)4]− anion. Magnetic measurements reveal that [2Dy][B(C6F5)4] is an SMM with a record anisotropy barrier up to 1277 cm−1 (1837 K) in zero field and a record magnetic blocking temperature of 60 K, including hysteresis with coercivity. The exceptional magnetic axiality of 2Dy is further highlighted by computational studies, which reveal this system to be the first lanthanide SMM in which all low‐lying Kramers doub…
Magnetic hysteresis up to 80 kelvin in a dysprosium metallocene single-molecule magnet
Breaking through the nitrogen ceiling Single-molecule magnets could prove useful in miniaturizing a wide variety of devices. However, their application has been severely hindered by the need to cool them to extremely low temperature using liquid helium. Guo et al. now report a dysprosium compound that manifests magnetic hysteresis at temperatures up to 80 kelvin. The principles applied to tuning the ligands in this complex could point the way toward future architectures with even higher temperature performance. Science , this issue p. 1400
Uranocenium: Synthesis, Structure, and Chemical Bonding
Abstraction of iodide from [(η5 -C5 i Pr5 )2 UI] (1) produced the cationic uranium(III) metallocene [(η5 -C5 i Pr5 )2 U]+ (2) as a salt of [B(C6 F5 )4 ]- . The structure of 2 consists of unsymmetrically bonded cyclopentadienyl ligands and a bending angle of 167.82° at uranium. Analysis of the bonding in 2 showed that the uranium 5f orbitals are strongly split and mixed with the ligand orbitals, thus leading to non-negligible covalent contributions to the bonding. Investigation of the dynamic magnetic properties of 2 revealed that the 5f covalency leads to partially quenched anisotropy and fast magnetic relaxation in zero applied magnetic field. Application of a magnetic field leads to domin…
Isolation of a perfectly linear uranium(II) metallocene
Reduction of the uranium(III) metallocene [(eta(5)-(C5Pr5)-Pr-i)(2)UI] (1) with potassium graphite produces the "second-generation" uranocene [(eta(5)-(C5Pr5)-Pr-i)(2)U] (2), which contains uranium in the formal divalent oxidation state. The geometry of 2 is that of a perfectly linear bis(cyclopentadienyl) sandwich complex, with the ground-state valence electron configuration of uranium(II) revealed by electronic spectroscopy and density functional theory to be 5f(3) 6d(1). Appreciable covalent contributions to the metal-ligand bonds were determined from a computational study of 2, including participation from the uranium 5f and 6d orbitals. Whereas three unpaired electrons in 2 occupy orbi…
Thermal expansion and magnetic properties of benzoquinone-bridged dinuclear rare-earth complexes.
The synthesis and structural characterization of two benzoquinone-bridged dinuclear rare-earth complexes [BQ(MCl2·THF3)2] (BQ = 2,5-bisoxide-1,4-benzoquinone; M = Y (1), Dy (2)) are described. Of these reported metal complexes, the dysprosium analogue 2 is the first discrete bridged dinuclear lanthanide complex in which both metal centres reside in pentagonal bipyramidal environments. Interestingly, both complexes undergo significant thermal expansion upon heating from 120 K to 293 K as illustrated by single-crystal X-ray and powder diffraction experiments. AC magnetic susceptibility measurements reveal that 2 does not show the slow relation of magnetization in zero dc field. The absent of …
CCDC 1551848: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Benjamin Day, Yan-Cong Chen, Ming-Liang Tong, Akseli Mansikamäkki|2017|Angew.Chem.,Int.Ed.|56|11445|doi:10.1002/anie.201705426
CCDC 1854466: Experimental Crystal Structure Determination
Related Article: Fu-Sheng Guo, Benjamin M. Day, Yan-Cong Chen, Ming-Liang Tong, Akseli Mansikkamäki, Richard A. Layfield|2018|Science|362|1400|doi:10.1126/science.aav0652
CCDC 1854468: Experimental Crystal Structure Determination
Related Article: Fu-Sheng Guo, Benjamin M. Day, Yan-Cong Chen, Ming-Liang Tong, Akseli Mansikkamäki, Richard A. Layfield|2018|Science|362|1400|doi:10.1126/science.aav0652
CCDC 1833613: Experimental Crystal Structure Determination
Related Article: Alexander F. R. Kilpatrick, Fu-Sheng Guo, Benjamin M. Day, Akseli Mansikkamäki, Richard A. Layfield, F. Geoffrey N. Cloke|2018|Chem.Commun.|54|7085|doi:10.1039/C8CC03516D
CCDC 1955099: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Nikolaus Tsoureas, Guo-Zhang Huang, Ming-Liang Tong, Akseli Mansikkamäki|2020|Angew.Chem.,Int.Ed.|59|2299|doi:10.1002/anie.201912663
CSD 1953092: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Nikolaus Tsoureas, Guo-Zhang Huang, Ming-Liang Tong, Akseli Mansikkamäki|2020|Angew.Chem.,Int.Ed.|59|2299|doi:10.1002/anie.201912663
CCDC 1551846: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Benjamin Day, Yan-Cong Chen, Ming-Liang Tong, Akseli Mansikamäkki|2017|Angew.Chem.,Int.Ed.|56|11445|doi:10.1002/anie.201705426
CCDC 1833614: Experimental Crystal Structure Determination
Related Article: Alexander F. R. Kilpatrick, Fu-Sheng Guo, Benjamin M. Day, Akseli Mansikkamäki, Richard A. Layfield, F. Geoffrey N. Cloke|2018|Chem.Commun.|54|7085|doi:10.1039/C8CC03516D
CCDC 2020929: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Benjamin Day, Yan-Cong Chen, Ming-Liang Tong, Akseli Mansikamäkki|2017|Angew.Chem.,Int.Ed.|56|11445|doi:10.1002/anie.201705426
CCDC 1840738: Experimental Crystal Structure Determination
Related Article: Benjamin M. Day, Fu-Sheng Guo, Sean R. Giblin, Akira Sekiguchi, Akseli Mansikkamäki, Richard A. Layfield|2018|Chem.-Eur.J.|24|16779|doi:10.1002/chem.201804776
CSD 1953094: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Nikolaus Tsoureas, Guo-Zhang Huang, Ming-Liang Tong, Akseli Mansikkamäki|2020|Angew.Chem.,Int.Ed.|59|2299|doi:10.1002/anie.201912663
CCDC 1898063: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Akseli Mansikkamaki, Ming-Liang Tong, Yan-Cong Chen|2019|Angew.Chem.,Int.Ed.|58|10163|doi:10.1002/anie.201903681
CCDC 1557625: Experimental Crystal Structure Determination
Related Article: Jani O. Moilanen, Akseli Mansikkamäki, Manu Lahtinen, Fu-Sheng Guo, Elina Kalenius, Richard A. Layfield, Liviu F. Chibotaru|2017|Dalton Trans.|46|13582|doi:10.1039/C7DT02565C
CCDC 1840737: Experimental Crystal Structure Determination
Related Article: Benjamin M. Day, Fu-Sheng Guo, Sean R. Giblin, Akira Sekiguchi, Akseli Mansikkamäki, Richard A. Layfield|2018|Chem.-Eur.J.|24|16779|doi:10.1002/chem.201804776
CCDC 1557624: Experimental Crystal Structure Determination
Related Article: Jani O. Moilanen, Akseli Mansikkamäki, Manu Lahtinen, Fu-Sheng Guo, Elina Kalenius, Richard A. Layfield, Liviu F. Chibotaru|2017|Dalton Trans.|46|13582|doi:10.1039/C7DT02565C
CSD 1953093: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Nikolaus Tsoureas, Guo-Zhang Huang, Ming-Liang Tong, Akseli Mansikkamäki|2020|Angew.Chem.,Int.Ed.|59|2299|doi:10.1002/anie.201912663
CCDC 1898062: Experimental Crystal Structure Determination
Related Article: Richard Layfield, Fu-Sheng Guo, Akseli Mansikkamaki, Ming-Liang Tong, Yan-Cong Chen|2019|Angew.Chem.,Int.Ed.|58|10163|doi:10.1002/anie.201903681
CCDC 1557623: Experimental Crystal Structure Determination
Related Article: Jani O. Moilanen, Akseli Mansikkamäki, Manu Lahtinen, Fu-Sheng Guo, Elina Kalenius, Richard A. Layfield, Liviu F. Chibotaru|2017|Dalton Trans.|46|13582|doi:10.1039/C7DT02565C
CCDC 1854467: Experimental Crystal Structure Determination
Related Article: Fu-Sheng Guo, Benjamin M. Day, Yan-Cong Chen, Ming-Liang Tong, Akseli Mansikkamäki, Richard A. Layfield|2018|Science|362|1400|doi:10.1126/science.aav0652
CCDC 1840739: Experimental Crystal Structure Determination
Related Article: Benjamin M. Day, Fu-Sheng Guo, Sean R. Giblin, Akira Sekiguchi, Akseli Mansikkamäki, Richard A. Layfield|2018|Chem.-Eur.J.|24|16779|doi:10.1002/chem.201804776
CCDC 1840736: Experimental Crystal Structure Determination
Related Article: Benjamin M. Day, Fu-Sheng Guo, Sean R. Giblin, Akira Sekiguchi, Akseli Mansikkamäki, Richard A. Layfield|2018|Chem.-Eur.J.|24|16779|doi:10.1002/chem.201804776