Silicon tetrafluoride nir spectrum

tricour's picture

Hi everybody,
i would like to know if someone had already tried to scan silicon tetrafluoride in gas with NIR gas cell ?
if yes i would be interested to share and discuss about experiment.
I know it is a tricky subject.

td's picture

Hi Tricour,

This is an interesting idea. Many years ago (about 1986) I tried to get support to research gas phase NIR spectra. At that time I was not aware that anyone had attempted it so I reasoned that we were bound to find something interesting but I failed to get a positive reaction.

Si F4 is going to be difficult (and potentially dangerous) but it you got a useful spectrum it would demonstrate possibilities. I found a NIST IR spectrum ( which shows a major absorption at about 1000 cm-1. Even the fourth overtone which would be around 2500nm would only just get into the NIR region. the other alternative might be a smaller peak at 1800cm-1 which would have a third overtone around 1850nm and a fourth around 1315nm.

I found an FTIR spectrum of SiF4 ( which shows peaks for three of the Si isotopes (28 -30). So the NIR peaks  (if you can get a spectrum) might be broadened.


I am sure you know that SIF4 is toxic, so take care and good luck.

Best wishes,