Publications by authors named "Miriam Kappe"

Infrared spectra of C60+ and C120+, obtained via helium messenger spectroscopy, are reported. For C60+, new absorption features have been found just above the discrete vibrational spectrum of the ion. The absorption profile, which is broad and contains little structure, is assigned to one or more electronic absorption transitions and is in good agreement with predictions from time-dependent density functional theory.

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The adsorption of helium on charged hexabenzocoronene (Hbc, CH), a planar polycyclic aromatic hydrocarbon (PAH) molecule of symmetry, was investigated by a combination of high-resolution mass spectrometry and classical and quantum computational methods. The ion abundance of HeHbc complexes versus size features prominent local anomalies at = 14, 38, 68, 82, and a weak one at 26, indicating that for these "magic" sizes, the helium evaporation energies are relatively large. Surprisingly, the mass spectra of anionic HeHbc complexes feature a different set of anomalies, namely at = 14, 26, 60, and 62, suggesting that the preferred arrangement of the adsorbate atoms depends on the charge of the substrate.

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We report the first helium-tagged electronic spectra of cationic adamantane clusters, along with its singly, doubly, and triply dehydrogenated analogues embedded in helium droplets. Absorption spectra were measured by recording the evaporation of helium atoms as a function of laser wavelength in the range of 300-2150 nm. Experimental spectra are coupled with simulated spectra obtained from quantum chemical calculations.

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Background: In the current literature, the outcome of paediatric brain injury is controversially discussed. According to the majority of the studies, there seems to be a decreased mortality but worse recovery in paediatric, traumatic brain injury in comparison with adults. However, there is a lack of information concerning the differences in various stages of development in patients younger than 18 years.

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