More Like this

1. Mechanochemical Reactivity of a Multimodal 2H-Bis-Naphthopyran Mechanophore

   https://doi.org/10.1039/d3py00344b  

   Osler, Skylar K. ; McFadden, Molly E. ; Zeng, Tian ; Robb, Maxwell J. ( June 2023 , Polymer Chemistry)

   Multimodal mechanophores that react under mechanical force to produce discrete product states with uniquely coupled absorption properties are interesting targets for the design of force-sensing polymers. Herein, we investigate the reactivity of a 2H-bis-naphthopyran mechanophore that generates thermally persistent mono-merocyanine and bis-merocyanine products upon mechanical activation in solution using ultrasonication, distinct from the thermally reversible products generated photochemically. We demonstrate that a force-mediated ester C(O)–O bond scission reaction following ring opening establishes an intramolecular hydrogen bond, locking one merocyanine subunit in the open form. Model compound studies suggest that this locked subunit confers remarkable thermal stability to bis-merocyanine isomers possessing a trans exocyclic alkene on the other subunit, implicating the formation of an unusual trans merocyanine isomer as the product of mechanochemical activation. Density functional theory calculations unexpectedly predict a thermally reversible retro-cyclization reaction of the bis-merocyanine species that could explain the mechanochemical generation of the unusual trans merocyanine isomer. 

   more » « less
2. Tetra‐ tert ‐butyl‐ s‐ indacene is a Bond‐Localized C 2h Structure and a Challenge for Computational Chemistry

   https://doi.org/10.1002/anie.202307379  

   Karas, Lucas J. ; Jalife, Said ; Viesser, Renan V. ; Soares, João V. ; Haley, Michael M. ; Wu, Judy I. ( September 2023 , Angewandte Chemie International Edition)

   Whether tetra‐tert‐butyl‐s‐indacene is a symmetricD_2hstructure or a bond‐alternatingC_2hstructure remains a standing puzzle. Close agreement between experimental and computed proton chemical shifts based on minima structures optimized at the M06‐2X, ωB97X‐D, and M11 levels confirm a bond‐localizedC_2hsymmetry, which is consistent with the expected strong antiaromaticity of TtB‐s‐indacene.

    

   more » « less
3. Synthesis and Properties of (BiSe) 0.97 MoSe 2 : A Heterostructure Containing Both 2H-MoSe 2 and 1T-MoSe 2

   https://doi.org/10.1021/acs.chemmater.9b01899  

   Hadland, Erik C. ; Göhler, Fabian ; Mitchson, Gavin ; Fender, Shannon S. ; Schmidt, Constance ; Zahn, Dietrich R. ; Seyller, Thomas ; Johnson, David C. ( August 2019 , Chemistry of Materials)

   null (Ed.)
4. First principles investigation of high thermal conductivity in hexagonal germanium carbide(2H-GeC)

   https://doi.org/10.1016/j.cartre.2021.100113  

   Muthaiah, Rajmohan ; Garg, Jivtesh ( October 2021 , Carbon Trends)
5. Collective 2p-2h intruder states in Sn118 studied via β decay of In118 using the GRIFFIN spectrometer at TRIUMF

   https://doi.org/10.1103/PhysRevC.102.024323  

   Ortner, K. ; Andreoiu, C. ; Spieker, M. ; Ball, G. C. ; Bernier, N. ; Bidaman, H. ; Bildstein, V. ; Bowry, M. ; Cross, D. S. ; Dunlop, M. R. ; et al ( August 2020 , Physical Review C)

   null (Ed.)