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1. Understanding the Mechanism of Secondary Cation Release from the (001) Surface of Li(Ni _1/3 Mn _1/3 Co _1/3 )O ₂ : Insights from First-Principles

   https://doi.org/10.1021/acs.jpcc.3c02764  

   Hudson, Blake G.; Jones, Diamond T.; Rivera Bustillo, Victoria M.; Bennett, Joseph W.; Mason, Sara E. (October 2023, The Journal of Physical Chemistry C)

   The transformations of complex metal oxides in aqueous settings must be studied to form a chemical understanding of how technologically relevant nanomaterials impact the environment upon disposal. Owing to the inherent heterogeneity and structural complexity of the ternary intercalation material Li(NixMnyCo1-x-y)O2 (NMC), the mechanisms of chemical processes at the solid–water interface are challenging to model. Here, density functional theory (DFT) + solvent ion methodology is used to study the energetics of stepwise release of two surface metals following unique pathways. The study spans different combinations of metal removal and also considers unique patterns of defects formed by modeling the NMC surface in supercells. The approach here also considers the equilibration of the surface with the surroundings between successive metal removals. A key finding is that a second metal removal prefers to proceed at a metal lattice site adjacent to the initial defect, and this is attributed in part to how the resulting slab with two metal vacancies maintains the most antiferromagnetic couplings between the remaining Ni/Mn. 

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2. Tuning In-Plane Magnetic Anisotropy and Interfacial Exchange Coupling in Epitaxial La _2/3 Sr _1/3 CoO ₃ /La _2/3 Sr _1/3 MnO ₃ Heterostructures

   https://doi.org/10.1021/acsami.3c10376  

   Feng, Mingzhen; Ahlm, Nolan; Sasaki, Dayne Y.; Chiu, I-Ting; N’Diaye, Alpha T.; Shafer, Padraic; Klewe, Christoph; Mehta, Apurva; Takamura, Yayoi (November 2023, ACS Applied Materials & Interfaces)
3. Tuning Relaxor-Antiferroelectric Order in (1 –  x )PbMg _1/3 Nb _2/3 O ₃ -( x )PbZrO ₃ Thin Films

   https://doi.org/10.1021/acsnano.5c06818  

   Pamula, Sreekeerthi; Pan, Hao; Denzer, Bridget R; Tian, Zishen; Surampalli, Akash; Park, Tae Joon; LeBeau, James M; Martin, Lane W (August 2025, ACS Nano)
4. An overview of oxygen vacancy dynamics in (1 − x )(Bi _1/2 Na _1/2 )TiO ₃ – x BaTiO ₃ solid solution

   https://doi.org/10.1039/d1tc02668b  

   Fan, Zhongming; Randall, Clive A. (January 2021, Journal of Materials Chemistry C)

   null (Ed.)

   (Bi 1/2 Na 1/2 )TiO 3 (BNT) based ceramics have been the hot topic for a few years because of their multiple functions, from the piezoelectric properties to more recently the electrostatic energy storage performance. However, some basic issues are still unclear, preventing their wide application in real devices. One of them is the underlying conduction mechanism, the interplay of electronic and ionic carriers as a mixed ionic case and the subsequent quantification. This paper deals with the most basic compositions, which are the typical ones from the (1 − x )(Bi 1/2 Na 1/2 )TiO 3 – x BaTiO 3 (BNT– x BT) phase diagram. The conductivity is primarily investigated by impedance spectroscopy, while different equivalent circuits are applied to different conduction mechanisms. A transition from predominantly ionic to predominantly electronic conduction is revealed to occur with the increase in BaTiO 3 concentration. The mixed ionic–electronic conduction in the composition near the morphotropic phase boundary, namely BNT–7%BT, is identified and then quantified. To verify our interpretation of impedance results, dc degradation is, for the first time, conducted in this family of materials, from which the electronic and ionic conductions can be easily separated by accessing the mean time to failure. The successful combination of the two methods enables us to have an overview of how the oxygen vacancy dynamics in the BNT– x BT system depends upon the phase nature or the domain structure. 

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5. Gradient chemical order in the relaxor Pb(Mg _1∕3 Nb _2∕3 )O ₃

   https://doi.org/10.1063/1.5016561  

   Cabral, Matthew J.; Zhang, Shujun; Dickey, Elizabeth C.; LeBeau, James M. (February 2018, Applied Physics Letters)