Applications of PulseTA® to the investigation of fluorides: An attempt to calibrate HF

Several procedures for the calibration of MS signals such as m/z = 19 (F+) representing hydrogen fluoride, HF, have been tested in order to achieve a reliable quantitative description of the thermal behaviour of fluorides and/or fluoride hydrates by applying the recent PulseTA® technique (PTA). Instead of desirable indirect calibration methods without the use of the corrosive HF, only the direct injection of 40% aqueous HF gave satisfying results. A differential calibration procedure, recently reported in literature, has been successfully applied. It will be demonstrated that both the calibration of m/z = 18 for water and m/z = 19 for hydrogen fluroride can be performed in a correct way for each mass number. But their joint application to the quantitaive description of a given compound revealed to be difficult if not impossible. This is interpreted in terms of the extreme properties of fluorides simultaneously liberating H2O and HF.