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1. Evolution of Ferromagnetic and Antiferromagnetic States in Iron Nitride Clusters Fe _n N and Fe _n N ₂ ( n = 1–10)

   https://doi.org/10.1021/acs.jpca.1c05769  

   Gutsev, Gennady L.; Aldoshin, Sergey M.; Gutsev, Lavrenty G.; Ramachandran, Bala R. (September 2021, The Journal of Physical Chemistry A)
2. Engineering Relaxor Behavior in (BaTiO ₃ ) _n /(SrTiO ₃ ) _n Superlattices

   https://doi.org/10.1002/adma.202302012  

   Lupi, Eduardo; Wexler, Robert_B; Meyers, Derek; Zahradnik, Anton; Jiang, Yizhe; Susarla, Sandhya; Ramesh, Ramamoorthy; Martin, Lane_W; Rappe, Andrew_M (November 2023, Advanced Materials)

   Abstract Complex‐oxide superlattices provide a pathway to numerous emergent phenomena because of the juxtaposition of disparate properties and the strong interfacial interactions in these unit‐cell‐precise structures. This is particularly true in superlattices of ferroelectric and dielectric materials, wherein new forms of ferroelectricity, exotic dipolar textures, and distinctive domain structures can be produced. Here, relaxor‐like behavior, typically associated with the chemical inhomogeneity and complexity of solid solutions, is observed in (BaTiO₃)_n/(SrTiO₃)_n(n= 4–20 unit cells) superlattices. Dielectric studies and subsequent Vogel–Fulcher analysis show significant frequency dispersion of the dielectric maximum across a range of periodicities, with enhanced dielectric constant and more robust relaxor behavior for smaller periodn. Bond‐valence molecular‐dynamics simulations predict the relaxor‐like behavior observed experimentally, and interpretations of the polar patterns via 2D discrete‐wavelet transforms in shorter‐period superlattices suggest that the relaxor behavior arises from shape variations of the dipolar configurations, in contrast to frozen antipolar stripe domains in longer‐period superlattices (n= 16). Moreover, the size and shape of the dipolar configurations are tuned by superlattice periodicity, thus providing a definitive design strategy to use superlattice layering to create relaxor‐like behavior which may expand the ability to control desired properties in these complex systems. 

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3. Minimal effect of stacking number on intrinsic cleavage and shear behavior of Ti _{n +1} AlC _n and Ta _{n +1} AlC _n MAX phases

   https://doi.org/10.1063/1.5026323  

   Son, Woongrak; Duong, Thien; Talapatra, Anjana; Prehn, Evan; Tan, Zeyi; Radovic, Miladin; Arróyave, Raymundo (June 2018, Journal of Applied Physics)
4. Anions Formed by Perchlorofluorobenzenes C ₆ Cl _n F _6–n ( n = 0–6)

   https://doi.org/10.1021/acs.jpca.4c04359  

   Sommerfeld, Thomas (September 2024, The Journal of Physical Chemistry A)

   Anions formed by the perhalobenzene series C$$_6$$Cl$$_{n}$$F$$_{6-n}$$ ($n=0-6$) are studied computationally. All members of the series form both stable valence and stable non-valence anions. At the geometry of the neutral parents, only non-valence anions are bound, and the respective vertical electron affinities show values in the $20$ to $60$meV range. Valence anions show distorted non-planar structures, and one can distinguish two types of conformers. A-type conformers show puckered-ring structures and excess electrons delocalized over several C-Cl bonds [in case of C$$_6$$F$$_6^-$$, C-F bonds], while B-type conformers possess excess electrons essentially localized in a single C-Cl bond, which is accordingly strongly stretched and bent out-of-plane. For a specific anion, all conformers are close in energy (relative energies of less than $10$kJ/mol) and are connected by low-lying transition states. Accordingly, A-type and B-type conformers possess similar adiabatic electron affinities, however, their vertical detachment energies exhibit drastically different values, which should ease conformer distinction in photoelectron spectroscopy. 

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5. Oxygen Incorporation in the Molecular Beam Epitaxy Growth of Sc _x Ga _1−x N and Sc _x Al _1−x N

   https://doi.org/10.1002/pssb.201900612  

   Casamento, Joseph; Xing, Huili Grace; Jena, Debdeep (January 2020, physica status solidi (b))

   Secondary‐ion mass spectrometry (SIMS) is used to determine impurity concentrations of carbon and oxygen in two scandium‐containing nitride semiconductor multilayer heterostructures: Sc_xGa_1−xN/GaN and Sc_xAl_1−xN/AlN grown by molecular beam epitaxy (MBE). In the Sc_xGa_1−xN/GaN heterostructure grown in metal‐rich conditions on GaN–SiC template substrates with Sc contents up to 28 at%, the oxygen concentration is found to be below 1 × 10¹⁹ cm⁻³, with an increase directly correlated with the scandium content. In the Sc_xAl_1−xN–AlN heterostructure grown in nitrogen‐rich conditions on AlN–Al₂O₃template substrates with Sc contents up to 26 at%, the oxygen concentration is found to be between 10¹⁹and 10²¹ cm⁻³, again directly correlated with the Sc content. The increase in oxygen and carbon takes place during the deposition of scandium‐alloyed layers. 

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