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1. Amplitude analysis of the D+ → π−π+π+ decay and measurement of the π−π+ S-wave amplitude

   https://doi.org/10.1007/JHEP06(2023)044  

   Aaij, R.; Abdelmotteleb, A. S.; Abellan Beteta, C.; Abudinén, F.; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Agapopoulou, C.; Aidala, C. A.; et al (June 2023, Journal of High Energy Physics)

   A bstract An amplitude analysis of the D + → π − π + π + decay is performed with a sample corresponding to 1.5 fb − 1 of integrated luminosity of pp collisions at a centre-of-mass energy $$ \sqrt{s} $$ s = 8 TeV collected by the LHCb detector in 2012. The sample contains approximately six hundred thousand candidates with a signal purity of 95%. The resonant structure is studied through a fit to the Dalitz plot where the π − π + S-wave amplitude is extracted as a function of π − π + mass, and spin-1 and spin-2 resonances are included coherently through an isobar model. The S-wave component is found to be dominant, followed by the ρ (770) 0 π + and f 2 (1270) π + components. A small contribution from the ω (782) → π − π + decay is seen for the first time in the D + → π − π + π + decay. 

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2. Hyperconjugative π → σ* _CF Interactions Stabilize the Enol Form of Perfluorinated Cyclic Keto–Enol Systems

   https://doi.org/10.1021/acs.joc.9b00825  

   Levandowski, Brian J.; Raines, Ronald T.; Houk, K. N. (April 2019, The Journal of Organic Chemistry)
3. Jet-Cooled Phosphorescence Excitation Spectrum of the T ₁ (n,π*) ← S ₀ Transition of 4 H -Pyran-4-one

   https://doi.org/10.1021/acs.jpca.3c01059  

   Parsons, Sean W.; Hucek, Devon G.; Mishra, Piyush; Plusquellic, David F.; Zwier, Timothy S.; Drucker, Stephen (April 2023, The Journal of Physical Chemistry A)
4. Laboratory and Astronomical Detection of the SiP Radical (X ² Π _i ): More Circumstellar Phosphorus

   https://doi.org/10.3847/2041-8213/ac9d9b  

   Koelemay, L. A.; Burton, M. A.; Singh, A. P.; Sheridan, P. M.; Bernal, J. J.; Ziurys, L. M. (November 2022, The Astrophysical Journal Letters)

   Abstract The millimeter-wave spectrum of the SiP radical (X²Π_i) has been measured in the laboratory for the first time using direct-absorption methods. SiP was created by the reaction of phosphorus vapor and SiH₄in argon in an AC discharge. Fifteen rotational transitions (J+ 1 ←J) were measured for SiP in the Ω = 3/2 ladder in the frequency range 151–533 GHz, and rotational, lambda doubling, and phosphorus hyperfine constants determined. Based on the laboratory measurements, SiP was detected in the circumstellar shell of IRC+10216, using the Submillimeter Telescope and the 12 m antenna of the Arizona Radio Observatory at 1 mm and 2 mm, respectively. Eight transitions of SiP were searched: four were completely obscured by stronger features, two were uncontaminated (J= 13.5 → 12.5 and 16.5 → 15.5), and two were partially blended with other lines (J= 8.5 → 7.5 and 17.5 → 16.5). The SiP line profiles were broader than expected for IRC+10216, consistent with the hyperfine splitting. From non-LTE radiative transfer modeling, SiP was found to have a shell distribution with a radius ∼300R_*, and an abundance, relative to H₂, off∼ 2 × 10⁻⁹. From additional modeling, abundances of 7 × 10⁻⁹and 9 × 10⁻¹⁰were determined for CP and PN, respectively, both located in shells at 550–650R_*. SiP may be formed from grain destruction, which liberates both phosphorus and silicon into the gas phase, and then is channeled into other P-bearing molecules such as PN and CP. 

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5. Solvent-Directed Assembly of π-Stacked 3D Metal–Organic Frameworks with Tunable Conductivity Enhanced by C ₆₀ Encapsulation

   https://doi.org/10.1021/jacs.5c04897  

   Tang, Xianhui; Wang, Xijun; Su, Shengyi; Wang, Xiaoliang; Xie, Haomiao; Li, Timothy Y-Z; Gong, Wei; Jia, Lei; Du, Enping; Xie, Ke; et al (June 2025, Journal of the American Chemical Society)

   Metal-organic frameworks (MOFs) with tunable structures and unique host-guest chemistry have emerged as promising candidates for conductive materials. However, the tunability of conductivity and porosity in conductive MOFs and their interrelationship still lack a systematic study. Herein, we report the synthesis of a series of 3D copper MOFs (NU-4000 to NU-4003) using a triphenylene-based hexatopic carboxylate linker. By modulating the ratio of mixed solvents, distinct structural topologies and π-π stacking arrangements were achieved, resulting in electrical conductivity ranging from insulators (˂ 10-6 S/cm) to semiconductors (10-8 ~ 102 S/cm). Among them, NU-4003 features continuous π-π stacking and exhibits a conductivity of 1.7 × 10-6 S/cm. To further enhance conductivity, we encapsulated C60, a strong electron acceptor, within the circular channels of NU-4003, resulting in a remarkable conductivity increase to 140 S/cm with approximately 100% pore occupancy. Even at lower C60 loadings that leave 54% of the pore volume remaining accessible, the conductivity remains exceptionally high at 104 S/cm. This represents an eight-order magnitude enhancement and positions NU-4003-C60 as one of the most conductive 3D MOFs reported to date. This work integrates two charge transport pathways (through-space and electron donor and acceptor) into a single MOF host-guest material, achieving a significant enhancement in conductivity. This study demonstrates the potential of combining host-guest chemistry and π-π stacking to design conductive MOFs with permanent porosity maintained, providing a blueprint for the development of next-generation materials for electronic and energy-related applications. 

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