The eigenstate-resolved 2q (acetylenic CH stretch) absorption spectrum of propyne has been observed for J’ =0-l 1 and K==O-3 in a skimmed supersonic molecular beam using optothermal detection. Radiation near 1.5 ,um was generated by a color center laser allowing spectra to be obtained with a full-width at half-maximum resolution of 6 x low4 cm-’ ( 18 MHz). Three distinct characteristics are obs...

High-resolution helium nanodroplet isolation spectra of the first overtone ~2n1) of the acetylenic stretch of several substituted acetylenes ~RC[C–H! at T50.38 K, have been observed for the first time. A tunable 1.5 mm laser is coupled, using a power buildup cavity, to a beam of He droplets seeded with the molecule to be studied. Absorption spectra are recorded by monitoring the beam depletion ...

The strong oxidant H2O2 is known to exist in solid form on Europa and is suspected to exist on several other Solar System worlds at temperatures below 200 K. However, little is known of the thermal chemistry that H2O2 might induce under these conditions. Here, we report new laboratory results on the reactivity of solid H2O2 with eight different compounds in H2O-rich ices. Using infrared spectro...

This paper describes ab initio electronic structure calculations on the planar transition states of 2-chloropropene leading to HCl elimination in the ground electronic state to form either propyne or allene as the cofragment. The calculations provide optimized geometries of the transition states for these two reaction channels, together with vibrational frequencies, barrier heights, and reactio...

The reactions of Y (a2D), Zr (a3F), Nb (a6D), Mo (a7S), and electronically excited-state Mo* (a5S) with propyne (methylacetylene) and 2-butyne (1,2-dimethylacetylene) were investigated using crossed molecular beams. For all of the metals studied, reactions with propyne led to H2 elimination, forming MC3H2. For Y + propyne, C-C bond cleavage forming YCCH + CH3 also was observed, with an energeti...

The reactions of ground-state atomic carbon with acetylene, (1), methylacetylene, (2), 22 3 ethylene, (3), and propylene, (4), are investigated at relative collision energies between 8.8 24 36 and 45 kJ mol~1 in crossed-beam experiments to elucidate the reaction products and chemical dynamics of atom-neutral encounters relevant to the formation of carbon-bearing molecules in the interstellar me...

The growth of a filamentous fungus, a Graphium sp., on n-alkanes (C(inf2) to C(inf4)) was inhibited by low concentrations of acetylene, propyne, 1-butyne, ethylene, and propylene. Acetylene and other unsaturated hydrocarbons had no effect on the growth of the Graphium sp. on potato dextrose broth, ethanol, or acetate. Our results suggest that n-alkynes and n-alkenes are selective inhibitors of ...

Electrical sensitivity of a Boron Nitride Nano Tube (BNNT) was examined toward hydroquinone (C6H4(OH)2), cyanogens (C2N2), methylacetylene (C3H4), ethylacetylene (C4H6), aniline (C6H5NH2), ethanol (C2H5OH), pyrrole (C4H...

Triflic anhydride (Tf2O) is the reagent of choice for the introduction of the trifluoromethylsulfonyl (CF3SO2) group into a variety of organic substrates, and the resulting compounds often have a unique chemical reactivity [1]. A case in point is given by 3-trifloxypropene iminium triflates which are obtained by O-sulfonylation of enaminones with Tf2O [2, 3] and which are suited for transformat...

Despite the growing use of renewable and sustainable biofuels in transportation, their combustion chemistry is poorly understood, limiting our efforts to reduce harmful emissions. Here we report on the (dissociative) ionization and the thermal decomposition mechanism of cyclopentanone, studied using imaging photoelectron photoion coincidence spectroscopy. The fragmentation of the ions is domina...