IR spectrum of an as-deposited sample of NMF in solid pH2, 29(4) ppm NMF concentration and 0.26(1) cm thickness, recorded at 1.86 K displaying the ν(N–CH3), ν(C–N), ν(C=O), ν(C–H), and ν(N–H) peaks of trans-NMF. The peak labeled cis-NMF is the ν(C=O) peak for cis-NMF. Peaks assigned to the trans-NMF dimer and the NMF complex with water are labeled D and W, respectively.
IR spectra (vertically offset) in the CO fundamental region from 2132 to 2152 cm−1 for (a) the same NMF doped pH2 sample shown in Figure 1 before photolysis, (b) after 150 s of 193 nm photolysis, and (c) for the as-deposited sample of a separate CO doped pH2 control experiment ([CO] = 9 ppm, l = 0.27(1) cm). Features previously assigned to CO isolated in fcc crystal sites are marked with asterisks and features only present in the photo-CO spectrum are labeled with the symbol #.
IR spectra (vertically offset) displaying the growth of the ν 9 (NH2-wag), ν 8 (C–N str), and ν 11 (CH3 d-str) absorption features of CH3NH2 with increasing exposure to the 193 nm photolysis laser for the same sample shown in Figure 1. The black, dark green, blue, light green, and red traces are recorded for total 193 nm photolysis (7.06 mW cm−2) exposures of 0, 60, 150, 270, and 510 s. Note the intensity for ν 8 and ν 11 are scaled by factors of 2 and 5, respectively.
IR spectra (vertically offset) displaying the ν(CN)+δ(NH), CH2-sci, ν a(C–H), and ν(N–H) absorption features of NHCH3 for the same sample and photolysis intervals depicted in Figure 3. Note that the intensities are scaled by the value indicated and the minor wavenumber scale is 1 cm−1 in all four spectral regions.
IR spectra (vertically offset) of the ν(C=O) stretch peak of the CONHCH3 radical for the same sample and photolysis intervals depicted in Figure 3.
IR spectra (vertically offset) displaying the ν 7, ν 8, ν 6, and ν 3 absorption features of CH2NH for the same sample and photolysis intervals depicted in Figure 3. The growth kinetics of this species indicates it is not a primary photolysis product. The intensities are scaled by the values indicated.
IR spectra (vertically offset) displaying the HNCO and CH3NCO asymmetric NCO stretch fundamentals (a) before and (b) after 510 s of photolysis for the same sample shown in Figure 3.
Concentration profiles as a function of photolysis time for the NMF doped pH2 sample depicted in Figure 3. Dotted circles represent the measured concentrations and the lines are fits to the appropriate two-step consecutive unimolecular kinetic equations. Part (a) plots the highest concentration species, (b) the primary photoproducts, and (c) a sampling of some of the secondary photoproducts.
Peak positions (FWHM) of the observed NMF features (cm−1).
Peak positions of the observed CH3NH2 features (cm−1) produced by photolysis of NMF.
Peak positions (cm−1) of the 193 nm photoproducts of NMF trapped in solid pH2 at 1.9 K. Calculated intensities (km/mol) and relative intensities are included for NHCH3 and CONHCH3.
Peak positions (cm−1) of the observed CH2NH features produced in the photolysis of NMF.
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