The Cosmic Ice Laboratory - IR Spectra
The Cosmic Ice Laboratory - IR Spectra
Links to IR spectra in various formats are available in the following tables. PLEASE NOTE: If you find these spectra helpful in your research, please acknowledge any use by reference to "Hudson et al." and this NASA web site.
Here are the types of spectra in the three tables below:
- Mid-IR Spectra of Molecules Diluted in H2O at 15 - 20 K
- Far-IR Spectra of H2O Ice
- IR Spectra of NH3-Containing Ices (See Moore, M. H., Ferrante, R. F., Hudson, R. L., and Stone, J. N. (2007). Ammonia—Water Ice Laboratory Studies Relevant to Outer Solar System Surfaces. Icarus, 190, 260-273.)
Mid-IR (4000-400 cm-1) Spectra of Molecules Diluted in H2O at 15 - 20 K
H2O + N2O (10:1)
Water + Nitrous Oxide (dinitrogen oxide) (10:1) at T = 18 K
Far-Infrared Spectra of H2O Ice (read a detailed description here)
H2O deposited at 14 K and subsequently warmed
deposit at 14 K
ASCII [28 kb]
warmed to 40 K
ASCII [25 kb]
warmed to 80 K
ASCII [26 kb]
warmed to 100 K
ASCII [25 kb]
warmed to 120 K
ASCII 24 kb]
warmed to 140 K
ASCII [24 kb]
warmed to 160 K
ASCII [24 kb]
IR Spectra of NH3-Containing Ices
** For details, see Moore, M. H., Ferrante, R. F., Hudson, R. L., and Stone, J. N. (2007). Ammonia–Water Ice Laboratory Studies Relevant to Outer Solar System Surfaces. Icarus, 190, 260-273. **
Figure 1
![A graph of the relative absorbance of NH3 comapred to H2O + NH3 at different temperatures. Shows increased activity arounf the 3400 cm-1 and 1000 cm-1.](spectra/ir-nh3/fig01.jpg)
NH3 compared to H2O+NH3 Ices
Figure 2
![Graph of the relative absorbance of H2O/NH3 mixtures at different temperatures and monohydrate versus hemihydrate. Shows increased acitivy around 1100 cm-1.](spectra/ir-nh3/fig02.jpg)
IR spectra of Ices made from H2O/NH3=0.5 gas-phase mixtures
Figure 3
![A graph showing the relative absorbtion of 'this work' compared to the hemihydrate reference spectrum (monohydrate is 2NH3 · H2O). Shows increased activity around the 3500 cm-1/3µm and 1000 cm-1 range.](spectra/ir-nh3/fig03.jpg)
This work compared to a hemihydrate reference spectrum
Figure 4
![A graph showing the relative absorbance of 'this work' compared to monohydrate reference spectrum (monohydrate is NH3 · H2O). Shows increased activity around the 3500 cm-1/3µm and 1000 cm-1 range](spectra/ir-nh3/fig04.jpg)
This work compared to a monohydrate reference spectrum
Figure 5
![A graph showing the relative absorbtion of 'this work' compared to the hemihydrate reference spectrum. Shows increased activity around the 1100 cm-1/~9 µm range.](spectra/ir-nh3/fig05.jpg)
The thermal evolution of hemihydrate 2NH3 � H2O
Figure 6
![Graph showing the thermal evolution of hemihydrate 2NH3 · H2O, Shows a sharp spike in activity around the 1100 cm-1 range.](spectra/ir-nh3/fig06.jpg)
A comparative look at near-IR spectra from 5400 to 4000 cm-1
Figure 7
![Graph comparing H2O, H2O + NH3, 2NH3 + H2O, and NH3. Shows spikes at the 5000 cm-1 and 4450 cm-1 range.](spectra/ir-nh3/fig07.jpg)
A comparative look at near-IR spectra from 5600 to 4000 cm-1
Figure 9
![Graph showing changes in the near- and mid-IR spectrum of 2NH3 · H20 at 50 Kelvin. Shows spikes at 5000 cm-1,= and 1100 cm-1.](spectra/ir-nh3/fig09.jpg)
Changes in the near- and mid-IR spectrum of 2NH3 � H2O at 50 K as a function of radiation dose
Figure 10
![Graph showing changes in the IR spectrum of 2NH3 · H2O before and after irradiation. Shows spikes at 1600 cm-1, 1100 cm-1 and 800 cm-1.](spectra/ir-nh3/fig10.jpg)
Changes in the IR spectrum of 2NH3 � H2O before and after an irradiation of 2.8 eV molecule-1