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Kingdon Trap. Hande Akbas Kealan Naughton Alexander Fuchs-Fuchs . Kingdon Trap. Kingdon Trap with SIMION. Create a working Kingdon trap in SIMION Results - Energy range of potentially trapped particles Improvements. What is a Kingdon Trap?. One of the first ion traps - PowerPoint PPT Presentation
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Kingdon Trap
Hande AkbasKealan Naughton
Alexander Fuchs-Fuchs
Kingdon Trap
Kingdon Trap with SIMION
•Create a working Kingdon trap in SIMION
•Results - Energy range of potentially trapped particles
•Improvements
What is a Kingdon Trap?•One of the first ion traps
•Radial trapping - two concentric cylinders with potential difference
•Axial trapping -ends with higher potential
•Ions are trapped in stable orbits if they possess the right angular momentum
•Static applied voltage results in a radial logarithmic potential between the electrodes
•Ions pulled in elliptical orbits
How it works
•Static applied voltage results in a radial logarithmic potential between the electrodes
•Ions pulled in elliptical orbits
The Kingdon Trap
•Symmetrical device•Inner cylinder a wire•Outer cylinder a hollow tube•Put caps on the ends
Theory•Maximum and minimum energies
defined by maximum and minimum orbits
•Energy Max: 768 eV
•Energy Minimum: 43 eV
The Trap
•Outer cylinder radius: 50 mm•Length: 300 mm•Inner cylinder: 5mm•The end caps separated by a few
mm
SIMION steps•Build the Geometry•Fly the first particles
Getting the particles inside
•Problem: Sealed cylinder•Make injection point•This addition must be kept same
potential as caps and outer cylinder, for uniform distribution
In action
Getting the particles inside
Defining the energy range
•Energy•Too High: Collide
with outer cylinder•Too Low: Collide with
inner rod
What we found•Inner rod Potential: -3200 V•Caps and cylinder: 20 V•Minimum energy: 43 eV (38 eV)•Max energy: 580 eV (768 eV)•Mass independent
Improvements
•Never been reported to produce mass spectra
•Modified version - Orbitrap - used as a mass spectrometer
Orbitrap•Type of mass spectrometer•outerbarrel-like electrode and
coaxial inner spindle like electrode•Electric field: quadro-logarithmic
potential distribution
Orbitrap•Oscillation frequency: independent
of ion velocity, Inversely proportional to square root. Characteristic of the mass of the particle
•High accuracy: 1-2 ppm•High resolving power: 200,000•resolving power proportional to the
number of harmonic oscillations
Conclusions
•Simulation of a working ion trap•Defined energy range agrees with
theory•Upgrades can be made into a
working mass spectrometer
Don’t get Caught