Can 222nm light cause UVIUVF, UVIVF, UVIIRF

[lukaszgryglicki]

Simple question, I didn't do any fluorescence photos yet and I'm just wondering about wavelenghts

- Assume I have 222nm UV light source, what kind of fluorescence can it create? Is there any rule about what wavelenghts cause what other wavelengths fluorescence?

 

I saw example of UV causing VIS Fluorescence and VIS causing IR, so I see shorter wave cause longer wave fluorescence, but how much longer - is there any limit? Say can 222nm (UV-C) cause 888nm (IR) F (4x longer wave)? Or maybe up to twice length or any other rule?

 

[StephanN]

https://en.wikipedia.org/wiki/Fluorescence

[lukaszgryglicki]

Well I saw that article, but it didn't answer my question it basically says that shorter wave creates longer wave F, mainly about UV->Vis, I asked if UV-C can cause other UV F (like UV-B, UV-A) or Vis or IR or all?

 

[StephanN]

Forgot the smiley, sorry 

 

In theory yes, but in practice, no idea, would need a book or site about physical chemistry to see if the 222 nm match the energy gap of a suitable material. This kind of match is the only restriction I know of, so no rule like only five times the wavelength. Perhaps some links can be found, starting from here: https://en.wikipedia.org/wiki/Photochemistry

[StephanN]

P.S.: https://en.wikipedia.org/wiki/Jablonski_diagram

[lukaszgryglicki]

Quote

 

In theory yes, but in practice, no idea
 

 

That's exacly why I asked :P actually I enjoy reading wiki for many many things all the time...

 

[Andy Perrin]

It's material-dependent, and there is no general rule aside from shorter wavelength illumination makes longer wavelength fluorescence (usually...there is also anti-Stokes effect, but that's so small it's usually hard to measure, and it's not quite the same phenomenon either). I know that's what StephanN said, but hopefully that summarizes! 

 

The fluorescence spectrum will typically have some kind of peak and die off as you go to longer and longer wavelengths. When I did the UV-induced IR fluorescence, the exposure time was much longer because there isn't as much of it. But no sharp cutoff in a scene that has hundreds of different types of molecules in it, each with their own fluorescence spectrum.

[dabateman]

@colinbm I think he has shown fluorescence with his 222nm light. 

If I had a 222nm light with tight filter,  it would be fun to see if I could see any emission using my uv bandpass filters.

I think even a 254nm light causes some fluorescence in uvb and uva. I still haven't played with that, but you have tryptophan with 280nm excitation and around 350nm emission.  Tyrosine excitation 270nm and emission is 310nm.

[colinbm]

Yes @dabateman Dave, I have shown UVIVF with my 222nm light, with a tight filter. 
But I have no way to see or record, if there is any shorter wavelength fluorescence the 350nm.