13967-06-1Relevant articles and documents
Microwave Spectrum, Inversion, and Molecular Structure of Monofluoramine, FNH2
Christen, D.,Minkwitz, R.,Nass, R.
, p. 7020 - 7024 (1987)
Microwave spectra of a new molecule, monofluoramine, and its deuterated isotopomers have been recorded and analyzed, yielding data on the molecular structure, dipole moment, quadrupole coupling, and barrier to inversion.The results are the following: A = 263 271.534 MHz, B = 26 357.357 MHz, C = 25 329.428 MHz, μa = 1.58 D, μc = 1.63 D, μtotal = 2.27 D, χaa = 7.16 MHz, χbb = -0.61 MHz, χcc = -6.55 MHz for the protonated species.The structural parameters are as follows: rNF = 143.29 pm, rNH = 102.25 pm, INV = 5200 cm-1.
Photochemistry of Fluorochloroamines in Low-Temperature Argon Matrices
Conklin, Robert A.,Gilbert, Julanna V.
, p. 3027 - 3031 (1990)
Broad-band and single-wavelength photolysis studies of NFCl2 and NF2Cl in low-temperature argon matrices have been carried out and the photolysis products identified via the IR spectra of the matrices.The photolysis energies were chosen on the basis of the UV absorption spectra, which for both compounds consist of single broad structureless features at 270 nm for NFCl2 and at 230 nm for NF2Cl.Broad-band photolysis and photolysis at 250, 270, and 300 nm of the NFCl2 matrix produced NF, as identified by the appearance of a peak at 1113 cm-1 in the IR spectrum.Photolysis of the NFCl2/Ar matrix at 210 and at 330 nm and of the NF2Cl/Ar matrix at 210, 245, and 330 nm produced no changes in the IR spectrum.Mechanisms are presented to explain these results.
The microwave spectrum of the NF radical in the second electronically excited (b 1Σ+) state: Potentials of three low-lying states (X3Σ-, a 1A, b1Σ+)
Kobayashi, Kaori,Saito, Shuji
, p. 6606 - 6610 (1998)
The pure rotational transition of the NF radical in the second electronically excited state, b 1Σ+, was detected by microwave spectroscopy. The NF radical was generated by dc-discharge through a mixture of NF3 and H2 at around 90 K. Six rotational transitions for v= 0 and four for v = 1 were observed in the 73-442 GHz region. In addition to the rotational and centrifugal distortion constants, the quadrupole coupling constant of the nitrogen nucleus of NF(b 1Σ+) was determined for the first time from the lowest two transitions of NF in the v = 0 level. The spectrum of NF(a 1Δ) in the first vibrational excited state was also observed in order to derive highly accurate potential parameters for comparison with the data of NF(X 3Σ-,b 1Σ+).
Kumar, S. V. K.,Sathyamurthy, N.,Manogaran, S.,Mitra, S. K.
, p. 465 - 470 (1994)
Tunable UV laser photolysis of NF2: Quantum yield for NF(a1Δ) production
Heidner, R. F.,Helvajian, Henry,Koffend, J. Brooke
, p. 1520 - 1524 (1987)
The UV photodissociation of NF2 has been investigated frorn 240-270 nm, using tunable UV radiation from a frequency upconverted YAG pumped dye laser system.The absorption cross section of NF2, and the photolysis quantum yield for the fragment NF(a1Δ) were measured with 0.25 cm-1 resolution.The NF(a1Δ) quantum yield decreases at longer wavelengths and is only 1 percent at 260 nm.This suggests that the first long wavelength band in NF2 leads primarily to ground state NF(X3Σ), and that the existence of a new higher lying NF2 electronic state is responsible for the NF(a1Δ) production.
Photolysis of FN3 at 193 nm
Patel, D.,Pritt, A. T.,Benard, D. J.
, p. 1931 - 1934 (1986)
The photolysis of FN3 by ArF excimer laser was found to yield both excited NF(b) and N2(A) photofragments in approimate yields of 5percent and 25percent, respectively.The photodissociation cross section at 193 nm was determined to be 2.8*10E-17 cm2 and the absorptin spectrum was recorded from 190 to 450 nm.The rates of NF(b) and N2(A) quenching by FN3 and NO were determined to be 8.7*10E5 and 1.1*10E6 torr1-s1-, respectively, and the heat of formation of FN3 was found to lie in the range of 120 to 135 kcal/mol.
Quenching Rate Constants of NF(a1Δ) at Room Temperature
Du, Kang Yan,Setser, D. W.
, p. 2425 - 2435 (1990)
The gas-phase quenching rate constants for NF(a1Δ) have been measured at 300 K for 60 reagent molecules.The experiments were done in a Pyrex glass flow reactor coated with halocarbon was using the 2F + HN3 reaction as a source of ND (a1Δ).The rate constants span a wide range of values; the rate constants for most diatomic molecules are less than 1E-14 cm3 molecule-1 s-1, but more reactive molecules, such as C2H4, NH3, or P(CH3)3, have rate constants near 1E-11 cm3 moleczule-1 s-1.For polyatomic reagents that can act as Lewis bases, a correlation was found between the magnitude of the quenching rate constant and the base strength (measured as the proton affinity) of the molecule, which is evidence that the closed-shell (?x2-?y2) component of the NF(a1Δ) state is involved in the quenching.The rate constants NF(a1Δ) are larger than for the analogous O2(a1Δ) state because of the more attractive interaction potentials between NF(a) and stable reagent molecules.A few experiments were done at ca. 200 K to demonstrate that this NF(a) source is suitable for low-temperature studies; the rate constants for O2, CO and C2H4 decreased with reduction in temperature.The 300 K bimolecular self-removal rate constant for NF(a1Δ) was assigned as (5 +/- 2) * 1E-12 cm3 molecule-1 s-1; bimolecular energy pooling by NF(a) to give NF(b) is not an important quenching pathway.Quenching of NF(a) by F atoms has a small rate constant, (4 +/- 2) * 1E-13 cm3 s-1.
The microwave spectrum of the NF radical in the metastable electronic state (a 1Δ)
Yamamoto, Satoshi,Saito, Shuji
, p. 102 - 105 (1987)
The microwave spectrum of the NF radical in the first electronically excited state a 1Δ has been observed in a dc glow discharge in a gaseous mixture of NF3 and H2.The transitions with J = 3-2 and 5-4 were observed in the 220 and 360 GHz regions, respectively.The rotational constant, centrifugal-distortion constant, and hyperfine coupling constants were determined precisely.The nuclear-spin rotation coupling constants for the F and N nuclei were obtained to be 99.1(7.5) and 13.5(6.3) kHz, respectively, with three standard deviations in parentheses.
The F + HN3 system: A chemical source for NF(a1Δ)
Habdas,Wategaonkar,Setser
, p. 451 - 458 (1987)
The secondary reaction in the F + HN3 reaction system under conditions of excess [F] provides a good source of NF(a1Δ) in a flow reactor. Comparison of the NF(a) yield from the F/HN3 system with the yield from the H/NF2 system suggests that ?85% of the HN3 can be converted to NF(a). The F + N3 secondary reaction has a rate constant of (5 ± 2) × 10-11 cm3 molecule-1 s-1. The primary reaction yields HF(v) with a distribution, P1-P4 of 36:36:22:06; the HF(v≥1) formation rate constant is (8.5 ± 0.9) × 10-11 cm3 molecule-1 s-1. From the highest observed HF(v,J) level, D0(H-N3) and ΔHf°0 (N3) were assigned as ≤93 and ≤113 kcal mol-1, respectively. Qualitative observations suggest a bimolecular NF(a) self-removal rate constant or a HF quenching rate constant of ～5 × 10-13 cm3 molecule-1 s-1.
Gas-Phase Chemistry of NF(a1Δ): Quenching Rate Constants
Quinones, E.,Habdas, J.,Setser, D. W.
, p. 5155 - 5158 (1987)
The reaction of excess F atoms with HN3 in a halocarbon-coated flow reactor has been used to generate and study the quenching reactions of NF(a1Δ, ν'=0) at 300 K.Fifteen reagents, selected to represent a variety of chemical interactions, were tested in order to provide a survey of quenching rate constants that could be compared to O2(a1Δg) and NH(a1Δ).A rang of rate constants was found which varied from ca. 1.0 x 1E-11 cm3 s-1 for N(CH3)3 to ca. 1.0 x 1E-15 cm3 s-1 for N2, H2, and NO.The NF(a1Δ) molecule is much less reactive than NH(a1Δ), and it seems to more closely resemble O2(a1Δg).However, the quenching rate constants for NH(a1Δ) generally are larger than for O2(a1Δg) and show a greater variation from one reagent to another.The self-quenching rate constant for NF(a1Δ) is (2.2 +/- 1.2) x 1E-12 cm3 s-1 with energy pooling to give NF(b1Σ+) being a small component of the total self-quenching reaction.
Zhan, Jiping,Huang, Ruiping,Zhunag, Qi,Zhang, Cunhao
, p. 568 - 574 (1990)
Generation of NBr(a1Δ) by the reaction of N3 radicals with Br atoms: A flow reactor source for quenching rate constant measurements
Hewett, Kevin B.,Setser
, p. 335 - 342 (2008/10/08)
The reaction between azide radicals (N3) and Br atoms is shown to produce electronically excited NBr(a1Δ) molecules in a room temperature flow reactor. This chemical system provides adequate concentration of NBr(a1Δ) so that this molecule can be systematically studied. The yield of NBr(b1Σ+) is minor. The quenching reactions of NBr(a) with HCl, HBr, HI, NH3, Br2, CF2Br2, and O2 were examined; the rate constants are (22 ± 5) × 10-14, (280 ± 30) × 10-14, (2300 ± 200) × 10-14, (35 ± 3) × 10-14, (2600 ± 300) × 10-14, (37 ± 6) × 10-14, and (230 ± 30) × 10-14 cm3 molecule-1 s-1, respectively.
