Publications by authors named "Robert J G Johnson"

The photothermal effect of nanoparticles has proven efficient for driving diverse physical and chemical processes; however, we know of no study addressing the dependence of efficacy on nanoparticle size. Herein, we report on the photothermal effect of three different sizes (5.5 nm, 10 nm and 15 nm in diameter) of magnetite nanoparticles (MNP) driving the decomposition of poly(propylene carbonate) (PPC).

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Magnetite nanoparticles (MNPs) show remarkable stability during extreme photothermal heating (≥770 K), displaying no change in size, crystallinity, or surfactants. The heat produced is also shown as chemically useful, driving the high-barrier thermal decomposition of polypropylene carbonate. This suggests MNPs are better photothermal agents (compared to gold nanoparticles), for photothermally driving high-barrier chemical transformations.

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The structure and torsional properties of oxalyl chloride fluoride in the gas phase have been measured by electron diffraction at temperatures of 22, 81, 158, and 310 °C. The molecule may be regarded as a hybrid of oxalyl chloride and oxalyl fluoride. Since the former exists as a more stable periplanar anti form (ϕ = 180°) in equilibrium with a less stable gauche form (ϕ ≃ 60°) and the latter as an equilibrium between two periplanar forms, anti and syn, the second form of oxalyl chloride fluoride is an interesting question.

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