Mass spectra of the isothiocyanato-derivatives of trimeric and tetrameric cyclophosphazenes

Abstract

The mass spectra of the isothiocyanato-derivatives of trimeric and tetrameric cyclophosphazenes have been obtained at an electron energy of 70 eV. The majority (80·85% for the trimer, 80·75% for the tetramer) of the fragmentation products are cyclic species, based on a N₃P₃ or N₄P₄ ring. The corresponding linear species N₂P₃ and N₃P₄ are absent. Fragmentation of the NCS groups takes place, either by the removal of a sulphur atom, the loss of a molecule S₂, or the loss of a molecule CS₂. Various processes, such as the removal of NCS groups, the decomposition of NCS groups, and, for the tetrameric fragments, contraction from the eight- to the six-membered ring, are visible in the form of metastable ions.