Roland Wester

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  • J Mikosch, S Trippel, C Eichhorn, R Otto, U Lourderaj, J X Zhang +3 others
  • 2008
Anion-molecule nucleophilic substitution (S(N)2) reactions are known for their rich reaction dynamics, caused by a complex potential energy surface with a submerged barrier and by weak coupling of the relevant rotational-vibrational quantum states. The dynamics of the S(N)2 reaction of Cl- + CH3I were uncovered in detail by using crossed molecular beam(More)
  • V Wakelam, E Herbst, J.-C Loison, I W M Smith, V Chandrasekaran, B Pavone +17 others
  • 2012
We present a novel chemical database for gas-phase astrochemistry. Named the KInetic Database for Astrochemistry (KIDA), this database consists of gas-phase reactions with rate coefficients and uncertainties that will be vetted to the greatest extent possible. Submissions of measured and calculated rate coefficients are welcome, and will be studied by(More)
We present the first observation of ultracold LiCs molecules. The molecules are formed in a two-species magneto-optical trap and detected by two-photon ionization and time-of-flight mass spectrometry. The production rate coefficient is found to be in the range 10 −18 cm 3 s −1 to 10 −16 cm 3 s −1 , at least an order of magnitude smaller than for other(More)
Helium has a unique phase diagram and below 25 bar it does not form a solid even at the lowest temperatures. Electrostriction leads to the formation of a solid layer of helium around charged impurities at much lower pressures in liquid and superfluid helium. These so-called 'Atkins snowballs' have been investigated for several simple ions. Here we form(More)
The proton transfer reaction H 3 + + CO is one of the cornerstone chemical processes in the interstellar medium. Here, the dynamics of this reaction have been investigated using crossed beam velocity map imaging. Formyl product cations are found to be predominantly scattered into the forward direction irrespective of the collision energy. In this process, a(More)
Ion-molecule reactions of the type X(-) + CH3Y are commonly assumed to produce Y(-) through bimolecular nucleophilic substitution (SN2). Beyond this reaction, additional reaction products have been observed throughout the last decades and have been ascribed to different entrance channel geometries differing from the commonly assumed collinear approach. We(More)
The existence of NCO(-) anions in the interstellar medium (ISM) has been suggested and searched for over the years but without any formal definitive sighting of that molecule. We discuss in this work the possible formation of either NCO(-) directly or of NCO neutral as a precursor to NCO(-) formation by electron attachment. We follow simple, gas-phase(More)
We recently reported the formation of ultracold LiCs molecules in the rovibrational ground state X1sigma+, v" = 0,J" = 0 (J. Deiglmayr et al., Phys. Rev. Lett., 2008, 101, 133004). Here we discuss details of the experimental setup and present a thorough analysis of the photoassociation step including the photoassociation line shape. We predict the(More)
We theoretically investigate pump-dump photoassociation of ultracold molecules with amplitude-and phase-modulated femtosecond laser pulses. For this purpose a perturbative model for the light-matter interaction is developed and combined with a genetic algorithm for adaptive feedback control of the laser pulse shapes. The model is applied to the formation of(More)
  • K M Mcguire, H Adler, P Alling, C Ancher, H Anderson, J L Anderson +192 others
  • 1995
After many years of fusion research, the conditions needed for a D-T fusion reactor have been approached on the Tokamak Fusion Test Reactor (TFTR). For the first time the unique phenomena present in a D-T plasma are now being studied in a laboratory plasma. The first magnetic fusion experiments to study plasmas using nearly equal concentrations of deuterium(More)
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