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1. State-to-state vacuum ultraviolet photodissociation study of CO ₂ on the formation of state-correlated CO(X ¹ Σ ⁺ ; v) with O( ¹ D) and O( ¹ S) photoproducts at 11.95–12.22 eV

   https://doi.org/10.1039/c5cp01321f  

   Lu, Zhou; Chang, Yih Chung; Benitez, Yanice; Luo, Zhihong; Houria, Adel Ben; Ayari, Tarek; Al Mogren, Muneerah Mogren; Hochlaf, M.; Jackson, W. M.; Ng, C. Y. (January 2015, Phys. Chem. Chem. Phys.)
2. Local structure elucidation of tungsten-substituted vanadium dioxide (V$$_{1-x}$$W$$_x$$O$$_2$$)

   https://doi.org/10.1038/s41598-022-18575-0  

   Wilson, Catrina E.; Gibson, Amanda E.; Cuillier, Paul M.; Li, Cheng-Han; Crosby, Patrice H. N.; Trigg, Edward B.; Najmr, Stan; Murray, Christopher B.; Jinschek, Joerg R.; Doan-Nguyen, Vicky (August 2022, Scientific Reports)

   Abstract Initially, vanadium dioxide seems to be an ideal first-order phase transition case study due to its deceptively simple structure and composition, but upon closer inspection there are nuances to the driving mechanism of the metal-insulator transition (MIT) that are still unexplained. In this study, a local structure analysis across a bulk powder tungsten-substitution series is utilized to tease out the nuances of this first-order phase transition. A comparison of the average structure to the local structure using synchrotron x-ray diffraction and total scattering pair-distribution function methods, respectively, is discussed as well as comparison to bright field transmission electron microscopy imaging through a similar temperature-series as the local structure characterization. Extended x-ray absorption fine structure fitting of thin film data across the substitution-series is also presented and compared to bulk. Machine learning technique, non-negative matrix factorization, is applied to analyze the total scattering data. The bulk MIT is probed through magnetic susceptibility as well as differential scanning calorimetry. The findings indicate the local transition temperature ($$T_c$$ $T_c$) is less than the average$$T_c$$ $T_c$supporting the Peierls-Mott MIT mechanism, and demonstrate that in bulk powder and thin-films, increasing tungsten-substitution instigates local V-oxidation through the phase pathway VO$$_2\, \rightarrow$$ ${}_2\to$V$$_6$$ ${}_6$O$$_{13} \, \rightarrow$$ ${}_{13}\to$V$$_2$$ ${}_2$O$$_5$$ ${}_5$. 

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3. Temperature-resolved surface infrared spectroscopy of CO on Rh(111) and (2 × 1)-O/Rh(111)

   https://doi.org/10.1116/6.0001932  

   Jamka, Elizabeth A.; Gillum, Maxwell Z.; Grytsyshyn-Giger, Christina N.; Lewis, Faith J.; Killelea, Daniel R. (July 2022, Journal of Vacuum Science & Technology A)

   Heterogeneously catalyzed reactions over transition metal surfaces are pillars of chemical industry and account for a significant fraction of the global energy demand. CO oxidation provides insight into the relative reactivity of various oxygenaceous surface phases, and it is necessary to first understand where it binds to the surface and the nature of the local environment to develop robust mechanistic pictures of the reaction. Surface IR spectroscopy is a quantitative technique that also provides information about the binding sites and chemical environments of the adsorbed CO molecules. Here, we report results from a study of CO sticking to clean Rh(111) and (2 × 1)-O/Rh(111) that shows that the intensity of the IR absorption was not linear with coverage and is an important consideration for further studies of the catalytic surface. 

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4. Orbital competition of Mn ³⁺ and V ³⁺ ions in Mn _1+x V _2-x O ₄

   https://doi.org/10.1088/1361-648X/abd9a1  

   Jiao, J L; Zhang, H P; Huang, Q; Wang, W; Sinclair, R; Wang, G; Ren, Q; Lin, G T; Huq, A; Zhou, H D; et al (January 2021, Journal of Physics: Condensed Matter)

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5. Intrinsic thermal expansion and tunability of thermal expansion coefficient in Ni-substituted Co ₂ V ₂ O ₇

   https://doi.org/10.1088/2515-7639/acfdce  

   Esteban, Erica T. B.; Garcia, Jasmine J.; Windover, Sophie R.; Cooley, Joya A. (October 2023, Journal of Physics: Materials)

   Abstract Framework oxide materials are well-known for exhibiting not only negative thermal expansion (NTE), but also demonstrating thermal expansion that can be controlled using composition as a tuning parameter. In this work, we study the intrinsic thermal expansion properties of Co₂V₂O₇, which has shown bulk linear NTE, and attempt to understand how substituting Ni²⁺for Co²⁺will affect the thermal expansion. The isomorphic solid solution is synthesized through solid-state methods and characterized using x-ray diffraction (XRD), diffuse reflectance spectroscopy, and neutron diffraction. The size difference between Ni²⁺and Co²⁺as well as the polyhedral volume of each Co²⁺metal coordination environment in the crystal structure allows Ni²⁺to partially be directed toward one crystallographic site over the other. Variable temperature synchrotron XRD data are employed to understand intrinsic thermal expansion. Across the solid solution, no intrinsic NTE is observed at the microscopic level, yet a degree of tunability in the thermal expansion coefficient with Ni substitution is demonstrated. The disparities between the intrinsic and bulk thermal expansion properties suggest that a morphological mechanism may have resulted in NTE in the bulk. 

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