On Jan 9, 2006, at 3:33 PM, Jones Beene wrote:
----- Original Message ----- From: "Horace Heffner"
Also of interest is that H2O absorbs energy at 190, 200, 250,
300, and 400 nm wavelengths.
Do you have a reference for these UV lines ?
Yes. It's the "UV Spectra of Common Liquids" section of the Handbook
of Chemistry and Physics, CRC Press,, 74th Edition, 1993-1994, page
9-166 (that's page 166 of section 9).
BTW the main cosmological frequencies used to spot water are the
H2O vapor absorption peaks at around 180 GHz and 320 GHz and there
is also strong microwave absorption of water at around 22 GHz. This
later one is not a simple rotational transition but it is the most
used by cosmologists, I have read, as the others are out of range
of inexpensive precision instrumentation.
That's interesting. I wonder how water does that. The 320 GHz, 180
GHz, and 22 GHz is around .0936 cm, 0.1666 cm, and 1.363 cm
wavelength respectively. That is to say I wonder how that tiny
molecule collects those giant wavelengths? It must be the effect
Bill Beaty talks about, where an antenna sets up its own field that
interferes with the big incoming signal and collects energy from it.
I never did understand that effect.
Do you have a reference on the those numbers? They sound handy.
Out of curiosity, the 190, 200, 250, 300, and 400 nm wavelengths are
157.8, 149.9, 119.9, 99.9, and 74.9 THz. Strange these don't agree
with yet overlap the vibrational frequencies of water:
symmetrical anti-symmetrical
bend stretch stretch
H2O 47.8 109.6 112.6
D2O 35.3 80.1 83.6
Table 2 - The vibrational frequencies of water molecule in THz.
I computed he above from table 3 - which comes from page 9-147 of the
same CRC Handbook as above.
symmetrical anti-symmetrical
bend stretch stretch
H2O 1595 3657 3756
D2O 1178 2671 2788
Table 3 - The vibrational wave number of water molecule in cm^-1.
Looks like I did that right. Interesting the vibration frequencies
don't relate to the absorption frequencies.
