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1. Solution and solid-state characterization of rare silyluranium( iii ) complexes

   https://doi.org/10.1039/d4cc00655k  

   Lin, Nathan J.; Zeller, Matthias; Bart, Suzanne C. (April 2024, Chemical Communications)

   A uranium(iii) silylate complex [K(DME)₄]-[UI₂{(Si(SiMe₃)₂SiMe₂)₂O}] (1) was stabilized by the addition of 18-crown-6 to form [K(18-crown-6)][UI₂{(Si(SiMe₃)₂SiMe₂)₂O}]. This species was fully characterized using multinuclear NMR spectroscopy, electronic absorption spectroscopy and X-ray crystallography. 

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2. Excited-state effects on magnetic properties of U( iii ) and U( iv ) pyrazolylborate complexes

   https://doi.org/10.1039/C9CC04800F  

   Higgins, Robert F.; Tatebe, Caleb J.; Bart, Suzanne C.; Shores, Matthew P. (August 2019, Chemical Communications)

   For a family of uranium pyrazolylborate complexes, we observe correlations between excited-state mixing and slow relaxation of magnetization for U( iii ) complexes, and U⋯B distances in U( iv ) complexes. 

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3. Validating dynamicity in resting state fMRI with activation‐informed temporal segmentation

   https://doi.org/10.1002/hbm.25649  

   Duda, Marlena; Koutra, Danai; Sripada, Chandra (December 2021, Human Brain Mapping)
4. Characterization of the Slow Molecular Dynamics of Poly( l ‐Lactic Acid) in α and α′ Phases, in a Glassy State, and in a Complex with Poly( d ‐Lactic Acid) by Solid‐State NMR

   https://doi.org/10.1002/macp.201700451  

   Chen, Wei; Zhou, Wenxuan; Makita, Yuta; Wang, Shijun; Yuan, Shichen; Konishi, Takashi; Miyoshi, Toshikazu (January 2018, Macromolecular Chemistry and Physics)

   Abstract Recently, slow molecular dynamics of poly(l‐lactic acid) (PLLA) by using 1D and 2D exchange NMR are investigated. In this work, slow molecular dynamics of PLLA chains in the α′, a stereocomplex (SC) with poly(d‐lactic acid), and glassy states are investigated in terms of centerband‐only detection of exchange (CODEX) NMR. The mixing‐time dependence of the CODEX data demonstrates that the molecular dynamics of stems become slower in the order of α′, α, and SC. The temperature dependence of the correlation time 〈τ_c〉 of the helical jump motions in the α and SC phases simply exhibits Arrhenius behaviors, with activation energy,E_a, values of 91 ± 1 and 97 ± 1 kJ mol⁻¹, respectively. In contrast, the temperature dependence of 〈τ_c〉 in the α′ sample exhibits two Arrhenius lines with substantially differentE_avalues of 273 ± 12 and 16 ± 14 kJ mol⁻¹at temperatures below and above 84 °C. The obtained kinetics of molecular dynamics not only establish the relationship between packing structure and dynamics in PLLA polymorphs and in the SC, but also allow for an understanding of the coupled dynamics between the crystalline and amorphous regions at approximatelyT_g. 

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5. Excited state processes of dinuclear Pt( ii ) complexes bridged by 8-hydroxyquinoline

   https://doi.org/10.1039/D3DT00348E  

   Kromer, Sarah; Roy, Subhangi; Yarnell, James E.; Taliaferro, Chelsea M.; Castellano, Felix N. (March 2023, Dalton Transactions)

   Dinuclear d 8 Pt( ii ) complexes, where two mononuclear square planar Pt( ii ) units are bridged in an “A-frame” geometry, possess photophysical properties characterised by either metal-to-ligand-(MLCT) or metal–metal–ligand-to-ligand charge transfer (MMLCT) transitions determined by the distance between the two Pt( ii ) centres. When using 8-hydroxyquinoline (8HQH) as the bridging ligand to construct novel dinuclear complexes with general formula [C^NPt(μ-8HQ)] 2 , where C^N is either 2-phenylpyridine (1) or 7,8-benzoquinoline (2), triplet ligand-centered ( 3 LC) photophysics results echoing that in a mononuclear model chromophore, [Pt(8HQ) 2 ] (3). The lengthened Pt–Pt distances of 3.255 Å (1) and 3.243 Å (2) results in a lowest energy absorption centred around 480 nm assigned as having mixed LC/MLCT character by TD-DFT, mirroring the visible absorption spectrum of 3. Additionally, 1 and 2 exhibit 3 LC photoluminescence with limited quantum yields (0.008) from broad transitions centred near 680 nm. Photoexcitation of 1–3 leads to an initially prepared excited state that relaxes within 15 ps to a 3 LC excited state centred on the 8HQ bridge, which then persists for several microseconds. All the experimental results correspond well with DFT electronic structure calculations. 

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