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1. Formation of Interstellar C60 From Silicon Carbide Circumstellar Grains

   https://doi.org/10.15278/isms.2019.WA01  

   Bernal, J; Haenecour, P.; Howe, J.; Zega, T.J.; . Amari, S.; Ziurys, L.M. (July 2019, The Astrophysical journal)

   We have conducted laboratory experiments with analog crystalline silicon carbide (SiC) grains using transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS). The 3C polytype of SiC was used—the type commonly produced in the envelopes of asymptotic giant branch (AGB) stars. We rapidly heated small (∼50 nm) synthetic SiC crystals under vacuum to ∼1300 K and bombarded them with 150 keV Xe ions. TEM imaging and EELS spectroscopic mapping show that such heating and bombardment leaches silicon from the SiC surface, creating layered graphitic sheets. Surface defects in the crystals were found to distort the six-membered rings characteristic of graphite, creating hemispherical structures with diameters matching that of C60. Such nonplanar features require the formation of five-membered rings. We also identified a circumstellar grain, preserved inside the Murchison meteorite, that contains the remnant of an SiC core almost fully encased by graphite, contradicting long-standing thermodynamic predictions of material condensation. Our combined laboratory data suggest that C60 can undergo facile formation from shock heating and ion bombardment of circumstellar SiC grains. Such heating/bombardment could occur in the protoplanetary nebula phase, accounting for the observation of C60 in these objects, in planetary nebulae (PNs) and other interstellar sources receiving PN ejecta. The synthesis of C60 in astronomical sources poses challenges, as the assembly of 60 pure carbon atoms in an H-rich environment is difficult. The formation of C60 from the surface decomposition of SiC grains is a viable mechanism that could readily occur in the heterogeneous, hydrogen-dominated gas of evolved circumstellar shells. 

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2. EWS Time Delay in Low Energy e−C60 Elastic Scattering

   https://doi.org/10.3390/atoms12030018  

   R, Aiswarya; Shaik, Rasheed; Jose, Jobin; Varma, Hari R; Chakraborty, Himadri S (March 2024, Atoms)

   Access to time delay in a projectile-target scattering is a fundamental tool in understanding their interactions by probing the temporal domain. The present study focuses on computing and analyzing the Eisenbud-Wigner-Smith (EWS) time delay in low energy elastic e−C60 scattering. The investigation is carried out in the framework of a non-relativistic partial wave analysis (PWA) technique. The projectile-target interaction is described in (i) Density Functional Theory (DFT) and (ii) Annular Square Well (ASW) static model, and their final results are compared in details. The impact of polarization on resonant and non-resonant time delay is also investigated. 

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3. Single-photon oxidation of C60 by self-sensitized singlet oxygen

   https://doi.org/10.1038/s42004-020-0318-x  

   Zhang, Linqi; Wang, Chong; Bao, Jiming; Kalkan, A. Kaan (December 2020, Communications Chemistry)

   null (Ed.)
4. Resistive Switching Characteristics of Fullerene (C60) in Polymannose Thin Film

   https://doi.org/10.1002/pssr.202200242  

   Cheong, Kuan Yew; Tayeb, Ilias Ait; Zhao, Feng (September 2022, physica status solidi (RRL) – Rapid Research Letters)

   The effects of C60 incorporated in polymannose‐based resistive switching memory have been systematically investigated for the first time in bioorganic‐based resistive switching memory. C60 with different concentrations (0–7 wt%) is dispersed in polymannose precursor, drop‐casted on ITO/PET substrate, and dried to form a thin film. Electrochemically inert Au–Pd is used as top electrode. The devices with embedded C60 show better endurance and stability. Read memory window decreases and ON/OFF ratio increases as the concentration of C60 increases. Stable retention time up to 10 years is achieved for all of the devices except the one with 7 wt% C60. Based on zeta potential measurement, polymannose is more negatively charged than C60. Hence, C60 functions as an effective interlock that bridges between long molecular chains of polymannose and enhances the resistive switching properties of the polymannose thin film. 

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5. Quantum scattering of icosahedron fullerene C60 with noble-gas atoms

   https://doi.org/10.1038/s41598-024-59481-x  

   Kłos, Jacek; Tiesinga, Eite; Kotochigova, Svetlana (April 2024, Scientific Reports)

   Abstract There exist multiple ways to cool neutral molecules. A front runner is the technique of buffer gas cooling, where momentum-changing collisions with abundant cold noble-gas atoms cool the molecules. This approach can, in principle, produce the most diverse samples of cold molecules. We present quantum mechanical and semiclassical calculations of the elastic scattering differential cross sections and rate coefficients of the C₆₀fullerene with He and Ar noble-gas atoms in order to quantify the effectiveness of buffer gas cooling for this molecule. We also develop new three-dimensional potential energy surfaces for this purpose using dispersion-corrected density functional theory (DFT) with counterpoise correction. The icosahedral anisotropy of the molecular system is reproduced by expanding the potential in terms of symmetry-allowed spherical harmonics. Long-range dispersion coefficients have been computed from frequency dependent polarizabilities of C₆₀and the noble-gas atoms. We find that the potential of the fullerene with He is about five times shallower than that with Ar. Anisotropic corrections are very weak for both systems and omitted in the quantum scattering calculations giving us a nearly quantitative estimate of elastic scattering observables. Finally, we have computed differential cross sections at the collision energies used in experiments by Han et al. (Chem Phys Lett 235:211, 1995), corrected for the sensitivity of their apparatus, and we find satisfactory agreement for C₆₀scattering with Ar. 

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