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1. Kinetics of the Topochemical Transformation of (PbSe) _m (TiSe ₂ ) _n (SnSe ₂ ) _m (TiSe ₂ ) _n to (Pb _0.5 Sn _0.5 Se) _m (TiSe ₂ ) _n

   https://doi.org/10.1021/jacs.8b10681  

   Sutherland, Duncan R.; Merrill, Devin R.; Ditto, Jeffrey; Moore, Daniel B.; Medlin, Douglas; Johnson, David C. (January 2019, Journal of the American Chemical Society)
2. Synthesis and Properties of the Helium Clathrate and Defect Perovskite [He _2–x □ _x ][CaNb]F ₆

   https://doi.org/10.1021/acs.jpcc.4c02174  

   Ma, Shangye; Hester, Brett R; Lloyd, Anthony J; dos_Santos, Antonio M; Molaison, Jamie J; Wilkinson, Angus P (July 2024, The Journal of Physical Chemistry C)
3. A support theorem for\break the Hitchin fibration: The case of GL _n and K _C

   https://doi.org/10.1515/crelle-2021-0045  

   de Cataldo, Mark Andrea; Heinloth, Jochen; Migliorini, Luca (August 2021, Journal für die reine und angewandte Mathematik (Crelles Journal))

   Abstract We compute the supports of the perverse cohomology sheaves of the Hitchin fibration for ${\mathrm{GL}}_n$ {\mathrm{GL}_{n}}over the locus of reduced spectral curves. In contrast to the case of meromorphic Higgs fields we find additional supports at the loci of reducible spectral curves. Their contribution to the global cohomology is governed by a finite twist of Hitchin fibrations for Levi subgroups. The corresponding summands give non-trivial contributions to the cohomology of the moduli spaces for every $n\ge 2$ {n\geq{2}}. A key ingredient is a restriction result for intersection cohomology sheaves that allows us to compare the fibration to the one defined over versal deformations of spectral curves. 

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4. LLAMA: The M _BH – σ _⋆ relation of the most luminous local AGNs

   https://doi.org/10.1051/0004-6361/201936321  

   Caglar, Turgay; Burtscher, Leonard; Brandl, Bernhard; Brinchmann, Jarle; Davies, Richard I.; Hicks, Erin K.; Koss, Michael; Lin, Ming-Yi; Maciejewski, Witold; Müller-Sánchez, Francisco; et al (February 2020, Astronomy & Astrophysics)

   Context. The M BH – σ ⋆ relation is considered a result of coevolution between the host galaxies and their supermassive black holes. For elliptical bulge hosting inactive galaxies, this relation is well established, but there is still discussion concerning whether active galaxies follow the same relation. Aims. In this paper, we estimate black hole masses for a sample of 19 local luminous active galactic nuclei (AGNs; LLAMA) to test their location on the M BH – σ ⋆ relation. In addition, we test how robustly we can determine the stellar velocity dispersion in the presence of an AGN continuum and AGN emission lines, and as a function of signal-to-noise ratio. Methods. Supermassive black hole masses ( M BH ) were derived from the broad-line-based relations for H α , H β , and Pa β emission line profiles for Type 1 AGNs. We compared the bulge stellar velocity dispersion ( σ ⋆ ) as determined from the Ca II triplet (CaT) with the dispersion measured from the near-infrared CO (2-0) absorption features for each AGN and find them to be consistent with each other. We applied an extinction correction to the observed broad-line fluxes and we corrected the stellar velocity dispersion by an average rotation contribution as determined from spatially resolved stellar kinematic maps. Results. The H α -based black hole masses of our sample of AGNs were estimated in the range 6.34 ≤ log M BH  ≤ 7.75 M ⊙ and the σ ⋆CaT estimates range between 73 ≤  σ ⋆CaT  ≤ 227 km s −1 . From the so-constructed M BH  −  σ ⋆ relation for our Type 1 AGNs, we estimate the black hole masses for the Type 2 AGNs and the inactive galaxies in our sample. Conclusions. We find that our sample of local luminous AGNs is consistent with the M BH – σ ⋆ relation of lower luminosity AGNs and inactive galaxies, after correcting for dust extinction and the rotational contribution to the stellar velocity dispersion. 

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5. The impact of site selectivity and disorder on the thermoelectric properties of Yb ₂₁ Mn ₄ Sb ₁₈ solid solutions: Yb ₂₁ Mn _4−x Cd _x Sb ₁₈ and Yb _21−y Ca _y Mn ₄ Sb ₁₈

   https://doi.org/10.1039/d1ma00497b  

   He, Allan; Cerretti, Giacomo; Kauzlarich, Susan M. (August 2021, Materials Advances)

   Thermoelectric materials can convert heat into electricity. They are used to generate electricity when other power sources are not available or to increase energy efficiency by recycling waste heat. The Yb 21 Mn 4 Sb 18 phase was previously shown to have good thermoelectric performance due to its large Seebeck coefficient (∼290 μV K −1 ) and low thermal conductivity (0.4 W m −1 K −1 ). These characteristics stem respectively from the unique [Mn 4 Sb 10 ] 22− subunit and the large unit cell/site disorder inherent in this phase. The solid solutions, Yb 21 Mn 4− x Cd x Sb 18 ( x = 0, 0.5, 1.0, 1.5) and Yb 21− y Ca y Mn 4 Sb 18 ( y = 3, 6, 9, 10.5) have been prepared, their structures characterized and thermoelectric properties from room temperature to 800 K measured. A detailed look into the structural disorder for the Cd and Ca solid solutions was performed using synchrotron powder X-ray diffraction and pair distribution function methods and shows that these are highly disordered structures. The substitution of Cd gives rise to more metallic behavior whereas Ca substitution results in high resistivity. As both Cd and Ca are isoelectronic substitutions, the changes in properties are attributed to changes in the electronic structure. Both solid solutions show that the thermal conductivities remain extremely low (∼0.4 W m −1 K −1 ) and that the Seebeck coefficients remain high (>200 μV K −1 ). The temperature dependence of the carrier mobility with increased Ca substitution, changing from approximately T −1 to T −0.5 , suggests that another scattering mechanism is being introduced. As the bonding changes from polar covalent with Yb to ionic for Ca, polar optical phonon scattering becomes the dominant mechanism. Experimental studies of the Cd solid solutions result in a max zT of ∼1 at 800 K and, more importantly for application purposes, a ZT avg ∼ 0.6 from 300 K to 800 K. 

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