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Title: Apparatus for reactive cluster-surface studies

Abstract

We present a new instrument that has been specifically designed for systematic studies of reactive cluster-surface collisions under well-defined ultrahigh-vacuum conditions. As a key feature, it incorporates a temperature-controlled, high-pressure cluster source with an unsurpassed pulse-to-pulse stability for the generation of weakly bound molecular aggregates. Impact processes can be investigated in two experimental configurations complementing one another: In the first, the exploration of intracluster reactions of accelerated, size-selected, positively or negatively charged cluster ions (1-100 eV/molecule) is accomplished, employing an inert target surface combined with angular-integrated ion detection. This arrangement uses a compact, homebuilt dual time-of-flight mass spectrometer with excellent mass resolution m/{delta}m>2000 and postacceleration capabilities. In the second configuration, the detailed analysis of chemical reactions between neutral clusters and a well-defined single crystal at lower kinetic energies (0.01-1 eV/molecule) is possible. Here, the surface interaction of a seeded supersonic cluster beam is probed with angular-, time-, and velocity-resolved detection of neutral reaction products using a high-performance quadrupole mass spectrometer.

Authors:
;  [1]
  1. Institut fuer Chemie, Humboldt-Universitaet zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin (Germany)
Publication Date:
OSTI Identifier:
20778569
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 77; Journal Issue: 1; Other Information: DOI: 10.1063/1.2162463; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CHEMICAL REACTIONS; CLUSTER BEAMS; CONFIGURATION; EQUIPMENT; ION DETECTION; ION PAIRS; KINETIC ENERGY; MASS RESOLUTION; MOLECULAR CLUSTERS; MONOCRYSTALS; PERFORMANCE; QUADRUPOLES; SURFACES; TIME RESOLUTION; TIME-OF-FLIGHT MASS SPECTROMETERS

Citation Formats

Christen, Wolfgang, and Rademann, Klaus. Apparatus for reactive cluster-surface studies. United States: N. p., 2006. Web. doi:10.1063/1.2162463.
Christen, Wolfgang, & Rademann, Klaus. Apparatus for reactive cluster-surface studies. United States. doi:10.1063/1.2162463.
Christen, Wolfgang, and Rademann, Klaus. Sun . "Apparatus for reactive cluster-surface studies". United States. doi:10.1063/1.2162463.
@article{osti_20778569,
title = {Apparatus for reactive cluster-surface studies},
author = {Christen, Wolfgang and Rademann, Klaus},
abstractNote = {We present a new instrument that has been specifically designed for systematic studies of reactive cluster-surface collisions under well-defined ultrahigh-vacuum conditions. As a key feature, it incorporates a temperature-controlled, high-pressure cluster source with an unsurpassed pulse-to-pulse stability for the generation of weakly bound molecular aggregates. Impact processes can be investigated in two experimental configurations complementing one another: In the first, the exploration of intracluster reactions of accelerated, size-selected, positively or negatively charged cluster ions (1-100 eV/molecule) is accomplished, employing an inert target surface combined with angular-integrated ion detection. This arrangement uses a compact, homebuilt dual time-of-flight mass spectrometer with excellent mass resolution m/{delta}m>2000 and postacceleration capabilities. In the second configuration, the detailed analysis of chemical reactions between neutral clusters and a well-defined single crystal at lower kinetic energies (0.01-1 eV/molecule) is possible. Here, the surface interaction of a seeded supersonic cluster beam is probed with angular-, time-, and velocity-resolved detection of neutral reaction products using a high-performance quadrupole mass spectrometer.},
doi = {10.1063/1.2162463},
journal = {Review of Scientific Instruments},
number = 1,
volume = 77,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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