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1. White light emission from co-doped La 2 Hf 2 O 7 nanoparticles with suppressed host → Eu 3+ energy transfer via a U 6+ co-dopant

   https://doi.org/10.1039/D1QI00134E  

   Gupta, Santosh K. ; Modak, Brindaban ; Modak, Pampa ; Mao, Yuanbing ( August 2021 , Inorganic Chemistry Frontiers)

   null (Ed.)

   Controlled energy transfer has been found to be one of the most effective ways of designing tunable and white photoluminescent phosphors. Utilizing host emission to achieve the same would lead to a new dimension in the design strategy for novel luminescent materials in solid state lighting and display devices. In this work, we have achieved controlled energy transfer by suppressing the host to dopant energy transfer in La 2 Hf 2 O 7 :Eu 3+ nanoparticles (NPs) by co-doping with uranium ions. Uranium acts as a barrier between the oxygen vacancies of the La 2 Hf 2 O 7 host and Eu 3+ doping ions to increase their separation and reduce the non-radiative energy transfer between them. Density functional theory (DFT) calculations of defect formation energy showed that the Eu 3+ dopant occupies the La 3+ site and the uranium ion occupies the Hf 4+ site. Co-doping the La 2 Hf 2 O 7 :Eu 3+ NPs with uranium ions creates negatively charged lanthanum and hafnium vacancies making the system highly electron rich. Formation of cation vacancies is expected to compensate the excess charge in the U and Eu co-doped La 2 Hf 2 O 7 NPs suppressing the formation of oxygen vacancies. This work shows how one can utilize the full color gamut in the La 2 Hf 2 O 7 :Eu 3+ ,U 6+ NPs with blue, green and red emissions from the host, uranium and europium, respectively, to produce near perfect white light emission. 

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2. Influence of Temperature and CO 2 On Plasma‐membrane Permeability to CO 2 and HCO 3 − in the Marine Haptophytes Emiliania huxleyi and Calcidiscus leptoporus (Prymnesiophyceae)

   https://doi.org/10.1111/jpy.13017  

   Blanco‐Ameijeiras, Sonia ; Stoll, Heather M. ; Zhang, Hongrui ; Hopkinson, Brian M. ; Raven, ed., J. ( June 2020 , Journal of Phycology)

   Membrane permeabilities to CO₂and HCO₃⁻constrain the function of CO₂concentrating mechanisms that algae use to supply inorganic carbon for photosynthesis. In diatoms and green algae, plasma membranes are moderately to highly permeable to CO₂but effectively impermeable to HCO₃⁻. Here, CO₂and HCO₃⁻membrane permeabilities were measured using an¹⁸O‐exchange technique on two species of haptophyte algae,Emiliania huxleyiandCalcidiscus leptoporus, which showed that the plasma membranes of these species are also highly permeable to CO₂(0.006–0.02 cm · s⁻¹) but minimally permeable to HCO₃⁻. Increased temperature and CO₂generally increased CO₂membrane permeabilities in both species, possibly due to changes in lipid composition or CO₂channel proteins. Changes in CO₂membrane permeabilities showed no association with the density of calcium carbonate coccoliths surrounding the cell, which could potentially impede passage of compounds. Haptophyte plasma‐membrane permeabilities to CO₂were somewhat lower than those of diatoms but generally higher than membrane permeabilities of green algae. One caveat of these measurements is that the model used to interpret¹⁸O‐exchange data assumes that carbonic anhydrase, which catalyzes¹⁸O‐exchange, is homogeneously distributed in the cell. The implications of this assumption were tested using a two‐compartment model with an inhomogeneous distribution of carbonic anhydrase to simulate¹⁸O‐exchange data and then inferring plasma‐membrane CO₂permeabilities from the simulated data. This analysis showed that the inferred plasma‐membrane CO₂permeabilities are minimal estimates but should be quite accurate under most conditions.

    

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3. Parity-Dependent Rotational Energy Transfer in CN(A 2 Π, ν = 4, j F 1 ε) + N 2 , O 2 , and CO 2 Collisions

   https://doi.org/10.1021/jp4123503  

   McGurk, Stephen J. ; Halpern, Joshua B. ; McKendrick, Kenneth G. ; Costen, Matthew L. ( March 2014 , The Journal of Physical Chemistry A)
4. An effective pathway to design and synthesize UV birefringent crystals via rational assembly of π-conjugated [CO 3 ] 2− and [NO 3 ] − triangles

   https://doi.org/10.1039/d2tc05374h  

   Hu, Zhaowei ; Liu, Lili ; Zhang, Ruixin ; Jing, Qun ; Wang, Huan ; Tian, Jindan ; Xu, Jiayue ; Halasyamani, P. Shiv ( March 2023 , Journal of Materials Chemistry C)

   Planar MO 3 (M = B, C, N) units have frequently been considered important structural components of novel birefringent crystal materials. An efficient approach for constructing new functional crystals is to simultaneously assemble multiple structural motifs together. Two compounds, Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O (X = Br and Cl), were synthesized by the integration of three kinds of anionic groups. More interestingly, the [CO 3 ] 2− and [NO 3 ] − groups in Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O are all coplanar with the aid of [NaO 7 ] 13− polyhedra, which can enhance the anisotropic polarizability. Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O have a large theoretical birefringence of ∼0.165 at 1064 nm and possess a short UV cut-off edge of ∼230 nm. Additionally, the two compounds exhibit good crystal growth habits. These properties illustrate that Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O are promising UV birefringent crystals. 

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5. Structural Motifs of [Fe(CO 2 ) n ] − Clusters ( n = 3–7)

   https://doi.org/10.1021/acs.jpca.7b02742  

   Thompson, Michael C. ; Dodson, Leah G. ; Weber, J. Mathias ( May 2017 , The Journal of Physical Chemistry A)