+44 1924 466555


Knudsen Effusion Mass Spectrometry

Knudsen Effusion Mass Spectrometry (KEMS) is a proven vapour pressure measurement technique capable of evaluating partial vapour pressures at high temperatures. By use of the Knudsen cell, KEMS provides quantitative, kinetic and thermodynamic information about isotopes and compounds contained in the analyte by assessing the gaseous emissions. The KEMS instrument from MSI is built on the proven AutoConcept platform.

Advantages of the AutoConcept platform:

  • Fully baked ion optics
  • Fully laminated magnet for fast scanning
  • Magnet range guaranteed from 1 amu
  • Minimal lenses which lend themselves to autotuning for assured sensitivity and resolution
  • Stable platform with modular ion optics to enable ease of installing of a glove box
  • Ultimate resolution of 80,000 enabling higher efficiency for routine applications
  • Dual filament for the EI source with trap and/or emission control
  • Heated and cooled ion source
  • Clip in ion source for ease of removal and maintenance with an option to remove the ion source through a lock system
  • Intermediate pumping to reduce loss of vacuum in the analyser region, keeping it clean from contamination

Key features of the KEMS from MSI:

  • Larger chamber for ease of assembly
  • X, Y and Z for alignment and minimal distance between orifice and EI chamber
  • Dual filament system
  • Laser /camera for alignment
  • Automatic pumping system
  • Ease of replacing sample
  • Accurate temperature measurement
  • Raised platform
  • Temperature control system
  • Complete system testing

The KEMS can be built according to customer specifications:

  • A custom designed glove box can be added (as pictured)
  • The furnace can be heated by means of either a laser or a resistance coil


KEMS under development

KEMS configurations

See our KEMS Applications page for more information.