More Like this

1. Dibridged, Monobridged, Vinylidene-Like, and Linear Structures for the Alkaline Earth Dihydrides Be 2 H 2 , Mg 2 H 2 , Ca 2 H 2 , Sr 2 H 2 , and Ba 2 H 2 . Proposals for Observations

   https://doi.org/10.1021/acs.inorgchem.0c01651  

   Narendrapurapu, Beulah S. ; Bowman, Michael C. ; Xie, Yaoming ; Schaefer, Henry F. ; Tkachenko, Nikolay V. ; Boldyrev, Alexander I. ; Li, Guoliang ( August 2020 , Inorganic Chemistry)
2. VUV Photoionization Cross Sections of HO 2 , H 2 O 2 , and H 2 CO

   https://doi.org/10.1021/jp508942a  

   Dodson, Leah G. ; Shen, Linhan ; Savee, John D. ; Eddingsaas, Nathan C. ; Welz, Oliver ; Taatjes, Craig A. ; Osborn, David L. ; Sander, Stanley P. ; Okumura, Mitchio ( February 2015 , The Journal of Physical Chemistry A)
3. Collision‐induced dissociation of [UO 2 (NO 3 ) 3 ] − and [UO 2 (NO 3 ) 2 (O 2 )] − and reactions of product ions with H 2 O and O 2

   https://doi.org/10.1002/jms.4705  

   Bubas, Amanda R. ; Perez, Evan ; Metzler, Luke J. ; Rissler, Scott D. ; Van Stipdonk, Michael J. ( February 2021 , Journal of Mass Spectrometry)

   Electrospray ionization (ESI) can produce a wide range of gas‐phase uranyl (UO₂²⁺) complexes for tandem mass spectrometry studies of intrinsic structure and reactivity. We describe here the formation and collision‐induced dissociation (CID) of [UO₂(NO₃)₃]⁻and [UO₂(NO₃)₂(O₂)]⁻. Multiple‐stage CID experiments reveal that the complexes dissociate in reactions that involve elimination of O₂, NO₂, or NO₃, and subsequent reactions of interesting uranyl‐oxo product ions with (neutral) H₂O and/or O₂were investigated. Density functional theory (DFT) calculations reproduce experimental results and show that dissociation of nitrate ligands, with ejection of neutral NO₂, is favored for both [UO₂(NO₃)₃]⁻and [UO₂(NO₃)₂(O₂)]⁻. DFT calculations also suggest that H₂O adducts to products such as [UO₂(O)(NO₃)]⁻spontaneously rearrange to create dihydroxides and that addition of O₂is favored over addition of H₂O to formally U(V) species.

    

   more » « less
4. Synthesis and crystallographic characterization of diphenylamide rare-earth metal complexes Ln (NPh 2 ) 3 (THF) 2 and [(Ph 2 N) 2 Ln (μ-NPh 2 )] 2

   https://doi.org/10.1107/S2056989020009998  

   Palumbo, Chad T. ; Kotyk, Christopher M. ; Ziller, Joseph W. ; Evans, William J. ( September 2020 , Acta Crystallographica Section E Crystallographic Communications)

   null (Ed.)

   Studies of the coordination chemistry between the diphenylamide ligand, NPh 2 , and the smaller rare-earth Ln III ions, Ln = Y, Dy, and Er, led to the structural characterization by single-crystal X-ray diffraction crystallography of both solvated and unsolvated complexes, namely, tris(diphenylamido-κ N )bis(tetrahydrofuran-κ O )yttrium(III), Y(NPh 2 ) 3 (THF) 2 or [Y(C 12 H 10 N) 3 (C 4 H 8 O) 2 ], 1-Y , and the erbium(III) (Er), 1-Er , analogue, and bis[μ-1κ N :2(η 6 )-diphenylamido]bis[bis(diphenylamido-κ N )yttrium(III)], [(Ph 2 N) 2 Y(μ-NPh 2 )] 2 or [Y 2 (C 12 H 10 N) 6 ], 2-Y , and the dysprosium(III) (Dy), 2-Dy , analogue. The THF ligands of 1-Er are modeled with disorder across two positions with occupancies of 0.627 (12):0.323 (12) and 0.633 (7):0.367 (7). Also structurally characterized was the tetrametallic Er III bridging oxide hydrolysis product, bis(μ-diphenylamido-κ 2 N : N )bis[μ-1κ N :2(η 6 )-diphenylamido]tetrakis(diphenylamido-κ N )di-μ 3 -oxido-tetraerbium(III) benzene disolvate, {[(Ph 2 N)Er(μ-NPh 2 )] 4 (μ-O) 2 }·(C 6 H 6 ) 2 or [Er 4 (C 12 H 10 N) 8 O 2 ]·2C 6 H 6 , 3-Er . The 3-Er structure was refined as a three-component twin with occupancies 0.7375:0.2010:0.0615. 

   more » « less
5. Temperature-dependent optical properties of monocrystalline CaF 2 , BaF 2 , and MgF 2

   https://doi.org/10.1364/OME.496246  

   Zheng, Qifan ; Wang, Xinchao ; Thompson, Dakotah ( July 2023 , Optical Materials Express)

   CaF₂, BaF₂, and MgF₂are low-index, infrared-transparent materials that are extensively used in optical systems. Despite their technological importance, a systematic investigation into the temperature dependence of their optical properties is lacking. In this study, spectroscopic ellipsometry was used to obtain the refractive index of monocrystalline CaF₂, BaF₂, and MgF₂for wavelengths between 220 nm and 1700 nm, and for temperatures between 21 °C and 368 °C. The raw ellipsometric data was fit to a Sellmeier model with temperature-dependent oscillator terms to extract the real part of the refractive index of each material. The refractive index of CaF₂and BaF₂was observed to decrease linearly with increasing temperature, which can be largely attributed to a reduction in the mass density due to thermal expansion. In contrast, the refractive index of MgF₂was found to vary nonlinearly with temperature, which suggests competing effects from the material’s electronic polarizability. The temperature-dependent refractive index data reported here provide a finely-resolved mapping of the thermo-optic coefficient for these three materials, which could inform the development of optical devices operating at elevated or unsteady temperatures.

    

   more » « less