The modification of residual gas analyzers to produce mass-selected ion beams

Miscellaneous · Mon Jan 01 00:00:00 EST 1990

OSTI ID:5943985

Gilbert, J R

The authors have constructed an instrument designed to trap mass-selected ions at low temperatures within a solid inert gas matrix for spectroscopic analysis. The goal was to construct a flexible instrument that would permit the study of a wide variety of mass-selected positive ions, and which could also be used to investigate the role that counterions play in the effective trapping of ionic species in inert cryogenic hosts. The instrument was designed to utilize both laser-induced fluorescence (LIF) and Fourier transform infrared (FTIR) spectroscopies to identify and investigate the structure of the trapped species. The sources employed in this experiment must produce high current ion beams for extended periods to allow the accumulation of a significant number of absorbers in the optical beam for FTIR investigation. Residual gas analyzers (RGAs) were selected as the basis for the mass-selected ion sources for this instrument. This dissertation focuses on the modification of two RGAs to produce controlled beams of mass-selected positive and negative ions that can be directed onto a remote surface for matrix isolation experiments. The discussion includes descriptions of the modifications made to the RGA ion sources and to a commercially available chemical ionization source to produce ions by surface emission, chemical ionization, and negative surface ionization. The mass-selected beams produced by the RGA quadrupoles were focused and deflected using a series of electrostatic optics. The design of these elements was optimized using computer modeling and ion beam visualization techniques. The modifications have allowed these RGAs to produce mass-selected ion beams that have been effectively used in the isolation of mass-selected ions within solid inert gas matrices.

• Research Organization: Michigan State Univ., East Lansing, MI (United States)
• OSTI ID: 5943985
• Resource Relation: Other Information: Thesis (Ph.D)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
COLD TRAPS
DESIGN
GASES
SPECTROSCOPY
ABSORPTION SPECTROSCOPY
COMPUTER-AIDED DESIGN
CRYOGENICS
FLUORESCENCE
FOURIER TRANSFORMATION
INFRARED RADIATION
ION BEAMS
IONIZATION
IONS
LASERS
MODIFICATIONS
SEPARATION EQUIPMENT
BEAMS
CHARGED PARTICLES
CONDENSERS
ELECTROMAGNETIC RADIATION
FLUIDS
INTEGRAL TRANSFORMATIONS
LUMINESCENCE
RADIATIONS
TRANSFORMATIONS
TRAPS
VAPOR CONDENSERS
400102* - Chemical & Spectral Procedures