I can still remember what the twin lines of the H2 spectrum looked like, because in physics 101 we used an old fashioned spectroscope and could actually see them.
Is there some technique that would allow you to actually see the emission spectrum of Ice? By, say laser exciting a single h20 molecule, or something equally technical?
It is done all of the time. Water is a contaminant or added (in digesting acid) in much emission spectroscopy.
But the H and O lines are swamped by the hydrogen and oxygen in the rest of the sample.
What exactly is the goal? Ice is solid water. I don’t think it has any unique emisson spectrum, it’ll be close to a blackbody. You can take ice and heat it up till it starts emitting spectral lines, but by that time the H2O isn’t
“ice”.
And in fact, it will have broken up into hydrogen and oxygen ions by the time it emits enough radiation to be measurable in a typical laboratory spectroscope. So it won’t be an emission spectrum of H2O.
Step 1, make a really cold chamber.
Step 2, calibrate your instruments with radiation from said chamber.
Step 3, stick a block of ice in there.
Step 4, spectrum of water ice.
Step 5, ah, this appears to confirm to theory and just have the spectrum of an H2O molecule additionally blurred by being in a solid.
But do you actually want the spectrum of water ice? You mention looking at a single molecule. The single molecule won’t tell you what the spectrum is like for ice, it will be identical (if you are insanely patient) to the spectrum of water vapor.
But do you actually want the spectrum of water ice? You mention looking at a single molecule. The single molecule won’t tell you what the spectrum is like for ice, it will be identical (if you are insanely patient) to the spectrum of water vapor.
Water vapor spectrum from 1924
And since emission spectra are inverse images of absorption spectra you can simplify your quest significantly by looking at absorption spectra instead. You’ll find that ice is too boring to go through the significantly complicated process of imaging directly.
Yes, thank you.
I actually /looked at/ the emission spectrum for H2. I just randomly thought that actually /looking at/ the emission spectrum for something would be interesting 
I guess I’d be stuck with looking at the absorption spectrum.
As to what it looks like … well that’s the point. How blurred is it? In the absorption/emission spectrum, is ice crystal-like? Or metal-like? I wouldn’t know without looking it up, and I certainly didn’t know when I started university.
Our H2 source was an electrically excited vacuum tube. You couldn’t do that with ice. You couldn’t do flame spectroscopy with ice. You can’t heat the entire block until it is radiating in the visible spectrum with ice. So the question was, is there anything you can do with ice that will give you a visible emission spectrum.
I don’t know what the MRI of ice looks like (except that it’s not visible), but perhaps that’s the closest technology allows us to get?
There’s no way ice can remain ice and still emit visible light, if that’s what you are asking.
MRI gives you radio frequency radiation from hydrogen atoms. How you get that to be like a visible light emission spectrum is beyond me.