Laser Raman Spectroscopy and Omegatron Mass Spectrometry Applied to Investigations of the Radiochemical Reactions Between Methane and Tritium

The radiochemical reactions between methane and tritium were vicariously chosen for the evaluation of an omegatron type mass spectrometer and a laser Raman spectrometer in view of their analytical application in tritium systems. Assessment of the omegatron was extended beyond previous work on the quantitative analysis of all hydrogen isotopes and stable helium isotopes to include the determination of tritiated hydrocarbons. As opposed to mass spectrometry, laser Raman spectroscopy is an absolute method, which in principle is applicable to all polyatomic gases. For the employment in tritium systems an uhv-tight stainless steel gas cell using windows mounted in CF flanges with a flatness better than 1 lambda was constructed and tested. The Raman spectra of H₂, HD and D₂ were measured and the pure rotation and rotation vibration branches assigned. The fundamental vibrations of methane and deuterated methanes have also been identified. First kinetic data on the β-radiation induced exchange reaction between tritium and methane have been obtained with an omegatron.