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1. Thermodynamic assessment of BaO–Ln ₂ O ₃ (Ln = La, Pr, Eu, Gd, Er) systems

   https://doi.org/10.1111/jace.17060  

   Gong, Weiping; Liu, Yanzhi; Xie, Yun; Zhao, Zhenting; Ushakov, Sergey V.; Navrotsky, Alexandra (February 2020, Journal of the American Ceramic Society)

   Abstract Heat capacities and enthalpies of formation of BaGd₂O₄were determined by high‐temperature differential scanning calorimetry and high‐temperature oxide melt solution calorimetry, respectively. Thermodynamic stability of BaLn₂O₄compounds increases with decreasing Ln³⁺ionic radius. Previously reported data on BaNd₂O₄and BaSm₂O₄corroborate this trend. Missing data for compounds in BaO–Ln₂O₃(Ln = La, Pr, Eu, Er) systems were estimated from established relations, thermodynamic assessment was performed, and binary phase diagrams were calculated. 

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2. Synthesis and reduction of [(C ₅ H ₄ SiMe ₃ ) ₂ Ln(μ-OR)] ₂ (Ln = La, Ce) complexes: structural effects of bridging alkoxides

   https://doi.org/10.1039/D4DT02137A  

   Brown, Adrian N; Kelleher, Jack N; Brown, Alexander M; Saghy, Peter; Bohl, Joshua J; Robinson, Jerome R; Huh, Daniel N (January 2024, Dalton Transactions)

   Alcoholysis of (C₅H₄SiMe)₃Ln results in bimetallic complexes with unexpected decreases in Ln⋯Ln distances as bridging alkoxides become bulkier. These complexes were characterized by DOSY NMR, CV, DPV, and a La^IIspecies was observed by EPR. 

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3. Evaluating electrochemical accessibility of 4f ⁿ 5d ¹ and 4f ⁿ⁺¹ Ln( ii ) ions in (C ₅ H ₄ SiMe ₃ ) ₃ Ln and (C ₅ Me ₄ H) ₃ Ln complexes

   https://doi.org/10.1039/D1DT02427B  

   Trinh, Michael T.; Wedal, Justin C.; Evans, William J. (October 2021, Dalton Transactions)

   The reduction potentials (reported vs. Fc + /Fc) for a series of Cp′ 3 Ln complexes (Cp′ = C 5 H 4 SiMe 3 , Ln = lanthanide) were determined via electrochemistry in THF with [ n Bu 4 N][BPh 4 ] as the supporting electrolyte. The Ln( iii )/Ln( ii ) reduction potentials for Ln = Eu, Yb, Sm, and Tm (−1.07 to −2.83 V) follow the expected trend for stability of 4f 7 , 4f 14 , 4f 6 , and 4f 13 Ln( ii ) ions, respectively. The reduction potentials for Ln = Pr, Nd, Gd, Tb, Dy, Ho, Er, and Lu, that form 4f n 5d 1 Ln( ii ) ions ( n = 2–14), fall in a narrow range of −2.95 V to −3.14 V. Only cathodic events were observed for La and Ce at −3.36 V and −3.43 V, respectively. The reduction potentials of the Ln( ii ) compounds [K(2.2.2-cryptand)][Cp′ 3 Ln] (Ln = Pr, Sm, Eu) match those of the Cp′ 3 Ln complexes. The reduction potentials of nine (C 5 Me 4 H) 3 Ln complexes were also studied and found to be 0.05–0.24 V more negative than those of the Cp′ 3 Ln compounds. 

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4. Toward 1D Transport in 3D Materials: SOC‐Induced Charge‐Transport Anisotropy in Sm ₃ ZrBi ₅

   https://doi.org/10.1002/adma.202404553  

   Khoury, Jason F; Han, Bingzheng; Jovanovic, Milena; Queiroz, Raquel; Yang, Xiao; Singha, Ratnadwip; Salters, Tyger H; Pollak, Connor J; Lee, Scott B; Ong, N P; et al (August 2024, Advanced Materials)

   Abstract 1D charge transport offers great insight into strongly correlated physics, such as Luttinger liquids, electronic instabilities, and superconductivity. Although 1D charge transport is observed in nanomaterials and quantum wires, examples in bulk crystalline solids remain elusive. In this work, it is demonstrated that spin‐orbit coupling (SOC) can act as a mechanism to induce quasi‐1D charge transport in the Ln₃MPn₅(Ln = lanthanide; M = transition metal; Pn = Pnictide) family. From three example compounds, La₃ZrSb₅, La₃ZrBi₅, and Sm₃ZrBi₅, density functional theory calculations with SOC included show a quasi‐1D Fermi surface in the bismuthide compounds, but an anisotropic 3D Fermi surface in the antimonide structure. By performing anisotropic charge transport measurements on La₃ZrSb₅, La₃ZrBi₅, and Sm₃ZrBi₅, it is demonstrated that SOC starkly affects their anisotropic resistivity ratios (ARR) at low temperatures, with an ARR of ≈4 in the antimonide compared to ≈9.5 and ≈22 (≈32 after magnetic ordering) in La₃ZrBi₅and Sm₃ZrBi₅, respectively. This report demonstrates the utility of spin‐orbit coupling to induce quasi‐low‐dimensional Fermi surfaces in anisotropic crystal structures, and provides a template for examining other systems. 

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5. Ultrafast Photofragmentation of Ln(hfac)3 with a Proposed Mechanism for forming High Mass Fluorinated Products

   https://doi.org/10.1038/s41598-020-64015-2  

   Chen, Jiangchao; Xing, Xi; Rey-de-Castro, Roberto; Rabitz, Herschel (April 2020, Scientific Reports)

   Abstract The photo-induced dissociative-ionization of lanthanide complexes Ln(hfac)₃(Ln = Pr, Er, Yb) is studied using intense ultrafast transform limited (TL) and linearly chirped laser pulses in a time-of-flight (TOF) mass spectrometry setup. Various fluorine and Ln-containing high-mass fragments were observed in this experiment, including the molecular parent ion, which have not been seen with previous studies relying on relatively long-duration laser pulses (i.e., ns or longer). These new high-mass observations provide important formerly missing information for deducing a set of photo-fragmentation mechanistic pathways for Ln(hfac)₃. An overall ultrafast control mechanism is proposed by combining insights from earlier studies and the fragments observed in this research to result in three main distinct photo-fragmentation processes: (a) ligand-metal charge transfer, (b) CF₃elimination, and (c) C-C bond rotation processes. We conclude that ultrafast dissociative-ionization could be a promising technique for generating high-mass fragments for potential use in material science applications. 

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