The reliability of Langmuir probe measurements for plasmaturbulence investigations is studied on GEMR gyro-fluid simulations and compared with the results from conditionally sampled I -V characteristics as well as electron-emitting probe measurements close to the last closed flux surface of the tokamak ASDEX Upgrade. In this region, simulation and experiment consistently show coherent in-phase fluctuations in density, plasma potential and also electron temperature. Ion-saturation current measurements turn out to reproduce density fluctuations quite well. Fluctuations in the floating potential, however, are strongly influenced by temperature fluctuations and, hence, are strongly distorted compared to the actual plasma potential. These results suggest that interpreting floating as plasma-potential fluctuations while disregarding temperature effects is not justified near the separatrix of hot fusion plasmas. Here, floating potential measurements led to corrupted results on the E × B dynamics of turbulent structures in the context of, e.g., turbulent particle and momentum transport or turbulence characterization on the basis of density-potential phase relations.

The reactions between chromium atoms and acetylene have been investigated in solid argon with infrared absorption spectroscopy. It is found that the ground-state chromium atoms reacted with acetylene to form the metallocyclopropene Cr(C2H2) molecule spontaneously on annealing. The Cr(C2H2) molecule underwent photochemical rearrangement to the alkynyl hydride HCrCCH molecule upon ultraviolet−visible irradiation. The two products were identified on the basis of isotopic IR studies with 13C2H2 and C2D2, and density functional theory calculations.

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The reactions of scandium atoms and methanol molecules have been investigated by matrix isolation infrared absorption spectroscopy. The reaction intermediates and products were identified on the basis of isotopic IR studies with 13 CH 3 OH, CH 3 18 OH, and CH 3 OD, as well as density functional theory calculations. In solid argon, the ground-state scandium atoms reacted with methanol to form the inserted CH 3 OScH molecules spontaneously but not the thermodynamically more favorable CH 3 ScOH. The inserted CH 3 OScH molecule underwent photochemical rearrangement to form the (CH 4 )OSc complex upon ultraviolet-visible irradiation. In addition, the CH 3 OSc molecule and its photoinduced CH 3 ScO isomer were also observed.

The reactions of magnesium atoms and methanol molecules have been investigated with matrix-isolation FTIR spectroscopy. In solid argon, the ground-state Mg atom reacted with methanol to form the Mg(CH 3 -OH) complex spontaneously on annealing. The complex underwent photochemical rearrangement to the methylmagnesium hydroxide (CH 3 MgOH) molecule upon ultraviolet-visible irradiation. The CH 3 MgOH molecule further reacted with a magnesium atom to form the CH 3 MgOMgH molecule. The aforementioned species were identified on the basis of isotopic IR studies with 13 CH 3 OH, CH 3 18 OH, and CH 3 OD, as well as density functional theory calculations.