NASA Ames PAH IR Spectroscopic Database

Transitions

Frequency [wavenumbers]	Wavelength [microns]	Integrated cross-section [km/mol]
3069	3.258	150.5
1942	5.15	2.408
1925	5.195	1.204
1920	5.208	1.204
1800	5.557	0.602
1792	5.582	1.204
1784	5.605	0.602
1779	5.621	0.602
1770	5.65	0.602
1756	5.694	10.23
1692	5.91	0.602
1615	6.193	7.826
1586	6.305	0.602
1506	6.641	7.826
1490	6.713	15.05
1476	6.777	1.204
1465	6.827	0.602
1451	6.89	50.57
1440	6.946	1.204
1430	6.993	13.24
1408	7.1	4.816
1374	7.275	2.408
1336	7.482	6.02
1266	7.902	4.816
1249	8.006	11.44
1238	8.077	1.806
1228	8.141	2.408
1207	8.288	5.418
1192	8.39	1.806
1151	8.687	1.204
1100	9.093	9.632
1057	9.459	2.408
1038	9.638	1.806
1023	9.778	4.816
998.6	10.01	0.602
967.2	10.34	0.602
950	10.53	4.816
883.5	11.32	32.51
873.4	11.45	1.204
823.7	12.14	54.18
803.9	12.44	0.602
773.6	12.93	48.16
743.6	13.45	60.2
684.7	14.6	1.204
620.9	16.11	3.01
601.3	16.63	6.622
585	17.09	1.204
554.3	18.04	5.418

Laboratory Spectrum

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This spectrum was measured using the matrix isolation technique. Samples are prepared by co-deposition of the PAH in the gaseous state with an overabundance of argon onto a cold CsI window suspended in a high vacuum chamber (p ~ 10-8 mtorr). The CsI window temperature is held between 10 and 15 K for the duration of the experiment. The infrared spectrum of the cold CsI window is recorded prior to (I₀) and immediately after sample deposition (I_n). The absorbance spectrum for a neutral, matrix isolated PAH is log(I_n/I₀).

By irradiating this matrix with ultraviolet radiation from a microwave powered hydrogen discharge lamp produces ionized PAHs. The infrared spectrum is again measured (I_i), now having absorption bands due to both the neutral and ionized PAH. This absorbance spectrum (log (I/I_i)) is compared with that of the neutral PAH. Most of the new bands produced by ultraviolet irradiation are due to the ionized form of the PAH. See the provided reference for the specific details regarding the data presented here. In some cases a few bands near 1600 cm^-1 may be due to H₂O.

Note(s):

The reported total integrated absorption cross-section for the CH_str band located around 3000 cm^-1 (3.3 μm) was established by disregarding any substructure seen in the band and simply integrating the entire feature, including any close-by bands.
Benzo[k]fluoranthene

You are kindly asked to consider the following references for citation when using the database:

C.W. Bauschlicher, Jr., A. Ricca, C. Boersma, L.J. Allamandola, "THE NASA AMES PAH IR SPECTROSCOPIC DATABASE: COMPUTATIONAL VERSION 3.00 WITH UPDATED CONTENT AND THE INTRODUCTION OF MULTIPLE SCALING FACTORS", The Astrophysical Journal Supplement Series, 234, 32, 2018 10.3847/1538-4365/aaa019 — BibTeX - RIS
C. Boersma, C.W. Bauschlicher, Jr., A. Ricca, A.L. Mattioda, J. Cami, E. Peeters, F. Sánchez de Armas, G. Puerta Saborido, D.M. Hudgins, and L.J. Allamandola, "THE NASA AMES PAH IR SPECTROSCOPIC DATABASE VERSION 2.00: UPDATED CONTENT, WEBSITE AND ON/OFFLINE TOOLS", The Astrophysical Journal Supplement Series, 211, 8, 2014 10.1088/0067-0049/211/1/8 — BibTeX - RIS
Mattioda, A. L., Hudgins, D. M., Boersma, C., Ricca, A., Peeters, E., Cami, J., Sánchez de Armas, F., Puerta Saborido, G., Bauschlicher, C. W., J., and Allamandola, L. J. "THE NASA AMES PAH IR SPECTROSCOPIC DATABASE: THE LABORATORY SPECTRA", The Astrophysical Journal Supplement Series, 251, 22, 2020 10.3847/1538-4365/abc2c8 — BibTeX - RIS