- Capture of nitrogen dioxide and conversion to nitric acid in a porous metal–organic framework
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Air pollution by nitrogen oxides, NOx, is a major problem, and new capture and abatement technologies are urgently required. Here, we report a metal–organic framework (Manchester Framework Material 520 (MFM-520)) that can efficiently confine dimers of NO2, which results in a high adsorption capacity of 4.2 mmol g–1 (298 K, 0.01 bar) with full reversibility and no loss of capacity over 125 cycles. Treatment of NO2?MFM-520 with water in air leads to a quantitative conversion of the captured NO2 into HNO3, an important feedstock for fertilizer production, and fully regenerates MFM-520. The confinement of N2O4 inside nanopores was established at a molecular level, and the dynamic breakthrough experiments using both dry and humid NO2 gas streams verify the excellent stability and selectivity of MFM-520 and confirm its potential for precious-metal-free deNOx technologies.
- Li, Jiangnan,Han, Xue,Zhang, Xinran,Sheveleva, Alena M.,Cheng, Yongqiang,Tuna, Floriana,McInnes, Eric J. L.,McCormick McPherson, Laura J.,Teat, Simon J.,Daemen, Luke L.,Ramirez-Cuesta, Anibal J.,Schr?der, Martin,Yang, Sihai
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- Interaction of copper with dinitrogen tetroxide in 1-butyl-3-methylimidazolium-based ionic liquids
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Ionic liquids that are stable toward oxidation and nitration and are based on the 1-n-butyl-3-methylimidazolium cation (BMIm+) can be used as solvents and reaction media for copper dissolution in liquid dinitrogen tetraoxide N2O4. The ionic liquid not only favors the dissociation of N2O4 into NO+ and NO3?, but also takes part in the formation of different crystalline products. Thus, NO[BF4], NO[Cu(NO3)3] and (BMIm)2[Cu2(CF3COO)6] were prepared using (BMIm)A, A? = [BF4]?, (CF3SO2)2N?, CF3COO?, respectively. The formation of a certain product is determined by the nature of the anion A? and the relative solubility of the reaction products in the ionic liquid. Crystals of NO[BF4] were also prepared directly from a mixture of N2O4 and BMImBF4. According to XRD single-crystal structure analysis, the structure of NO[BF4] consists of tetrahedral [BF4]? anions and nitrosonium NO+ cations; the formation of these ions prove the heterolytic dissociation of N2O4 dissolved in the ionic liquid. The crystal structure of the earlier unknown binuclear copper trifluoroacetate (BMIm)2[Cu2(CF3COO)6] were determined by X-ray diffraction. The peculiarity of this dimer compared to the majority of known dimeric copper(ii) carboxylates is the unusually long Cu?Cu distance (3.15 ?), with Cu(ii) ions demonstrating an atypical coordination of a distorted trigonal bipyramid formed by five O atoms of five trifluoroacetate groups.
- Morozov,Deeva,Glazunova,Troyanov,Guseinov,Kustov
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- Nitropyrene Photoprobes: Making Them, and What Are They Good for?
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Pyrene derivatives are among the most widely used organic fluorescent photoprobes. Many of them are photosensitizers for hole injection. Pyrenes, however, are mostly UV absorbers, limiting their utility for photonic applications. Nitration of pyrene shifts its absorption to the visible region. Conversely, nitration of pyrene that is already derivatized for covalent labeling, produces mixtures of isomers that are challenging to separate. We present a robust procedure for attaining isomerically pure nitropyrenes. NMR analysis provides unequivocal assignments of the regioisomers and of the structures of the disubstituted nitropyrenes. The added substituents negligibly affect the electronic properties of the nitropyrenes. Photoexcited nitropyrenes undergo efficient triplet formation, making them an attractive choice for triplet sensitizers and photooxidants. Hence, facile and reliable preparation of disubstituted nitropyrenes provides venues for exploring their electronic and photonic utility.
- Espinoza, Eli M.,Xia, Bing,Darabedian, Narek,Larsen, Jillian M.,Nu?ez, Vicente,Bao, Duoduo,Mac, Jenny T.,Botero, Fabian,Wurch, Michelle,Zhou, Feimeng,Vullev, Valentine I.
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- Explosive Thermal Decomposition Mechanism of RDX
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Thin films of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) have been subjected to transient pyrolysis using a pulsed CO2 laser in order to determine details of the thermal decomposition mechanism under conditions that simulate a thermal explosion.The first step, scission of an N-N bond, leads to formation of N2O4.The product is trapped in the solid film by rapid quenching to 77 K following the pyrolysis pulse and subsequently detected by transmission FTIR spectroscopy of the film.Product yield measurements show that 1.9 +/- 0.2 RDX molecules are destroyed for every N2O4 molecule detected in the films.Crossover experiments conducted on isotopically labeled samples containing both unlabeled and fully labeled RDX-(15)N6 show that the N2O4 product consists of a statistical mixture of (14,14)N2O4, (14,15)N2O4, and (15,15)N2O4 isotopomers.These results show that both halves of the dimer arise from separate RDX parent molecules and the explosive decomposition of RDX involves loss of only a single NO2 molecule.
- Botcher, Tod R.,Wight, Charles A.
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- Low-Temperature Trapping of Intermediates in the Reaction of NO? with O2
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The autoxidation of NO? was studied in glass-like matrices of 2-methylbutane at 110 K and in a 8:3 v/v mixture of 2,2-dimethylbutane and n-pentane (rigisolve) at 80-90 K, by letting gaseous NO? diffuse into these solvents that were saturated with O2. In 2-methyllbutane, we observed a red compound. However, in rigisolve at 85-90 K, a bright yellow color appears that turns red when the sample is warmed by 10-20 K. The new yellow compound is a precursor of the red one and also diamagnetic. The UV-vis spectrum of the yellow compound contains a band which resembles that present in ONOO-. Because the red and yellow intermediates are not paramagnetic, we postulate that ON-O-O? is in close contact with NO?, or with another ON-O-O?. Diffusion of gaseous O2 into rigisolve saturated with NO? does not produce a color; however, a weak EPR signal (g = 2.010) is observed. This signal most likely indicates the presence of ONOO?. These findings complement our earlier observation of a red color at low temperatures and the presence of ONOO? in the gas phase (Galliker, B.; Kissner, R.; Nauser, T.; Koppenol, W. H. Chem. Eur. J. 2009, 15, 6161-6168), and they indicate that the termolecular autoxidation of nitrogen monoxide proceeds via the intermediate ONOO? and not via N2O2
- Mahmoudi, Leila,Kissner, Reinhard,Koppenol, Willem H.
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- Falloff Curve and Secific Rate Constants for the Reaction NO2+NO2N2O4
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The rate of association of NO2 to N2O4 was measured in N2 at pressures from 1 to 207 bar.This way the reaction was observed in a large section of its falloff range.The relaxation of NO2/N2O4 mixtures was followed after laser flash photolysis of N2O4 at 248 nm.From the results the falloff curve was constructed, which gives the high- and low-pressure rate constants at 298 K (in cm3 molecule-1 s-1): kassinfinite=(8.3+/-1.0)*10-13 and kass0=(1.4+/-0.2)*10-33.Earlier measurements, believed to be in the low-pressure regime, have not been free from falloff effects.The low value of kinfinite was analyzed with the statistic adiabatic chanell model, and specific rate constants, k(E,J), were calculated.They increase very steeply with energy just above the reaction treshold and go through maxima at low excess energies.These unusual effects are analyzed theoretically and the strong contributions are pointed out of the low-frequency vibrations which disappear during the dissociation of N2O4.
- Borrell, Peter,Cobos, C. J.,Luther, K.
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- Highly efficient reversible adsorption of NO2 in imidazole sulfonate room temperature ionic liquids
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The highly efficient reversible adsorption of NO2 in room-temperature ionic liquids is reported for the first time, making a platform for promising applications.
- Yuan, Gang,Zhang, Feng,Geng, Jiao,Wu, You-Ting
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- Reactive species generated during wet chemical etching of silicon in HF/HNO3 mixtures
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The role of intermediate species generated during wet chemical etching of silicon in a HF-rich HF/HNO3 mixture was studied by spectroscopic and analytical methods at 1°C. The intermediate N2O3 was identified by its cobalt blue color and the characteristic features in its UV-vis and Raman spectra. Furthermore, a complex N(III) species (3NO +·NO3-) denoted as [N4O 62+] is observed in these solutions. The time-dependent decay of the N(III) intermediates, mainly by their oxidation at the liquid-air interface, serves as a precondition for the study of the etch rate as function of the intermediate concentration measured by Raman spectroscopy. From a linear relationship between etch rate and [N4O62+] concentration, NO+ is considered to be a reactive species in the rate-limiting step. This step is attributed to the oxidation of permanent existing Si-H bonds at the silicon surface by the reactive NO+ species. N2O3 serves as a reservoir for the generation of NO+ leading to a complete coverage of the silicon surface with reactive species at high intermediate concentrations. As long as this condition is valid (plateau region), the etch rate is constant and yields a smooth silicon surface upon completion of the etching. If the N2O3 concentration is insufficient to ensure a coverage of the Si surface by NO +, the etch rate decreases linearly with the N2O 3 concentration and results in a roughening of the etched silicon surface (slope region).
- Steinert, Marco,Acker, Joerg,Krause, Matthias,Oswald, Steifen,Wetzig, Klaus
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- Observation of paramagnetic Raman optical activity of nitrogen dioxide
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Raman optical activity (ROA) detects the intensity difference between right and left circularly polarized scattered light, and thus brings about enhanced information about the molecules under investigation. The difference is quite small and the technique is mostly constrained to the condensed phase. For NO2 in the presence of a static magnetic field, however, the ROA signal with high ROA/Raman intensity ratio was observed. The signal is so strong owing to molecular paramagnetism and a pre-resonance signal enhancement. The spectral shape was explained on the basis of the Fermi golden rule and rotational wave functions expanded to a spherical top basis. The results indicate that the technique can be immediately used to obtain information about molecular properties, such as polarizability components. It also has a potential to detect other paramagnetic gases and discriminate among them. Paramagnetic gases: Paramagnetic Raman optical activity of nitrogen dioxide was observed for the first time and explained on the basis of angular momentum theory (see picture). The technique provides enhanced information about molecular properties, and the results suggest that the technique can be immediately used for discrimination and analysis of similar paramagnetic gases.
- Sebestik, Jaroslav,Bour, Petr
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- Infrared spectra and UHF SCF calculations of HF complexes with NO, (NO)2, and NO2
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HF complexes with nitric oxide and nitrogen dioxide were prepared in argon matrices and studied using IR spectroscopy and unrestricted Hartree-Fock SCF calculations.The results indicate the formation of three different complexes NO--HF, ONNO--HF, and ONO--HF, in which the hydrogen atom of HF is bound to an oxygen atom of the base in each complex.Perturbations in the N-O stretching base submolecule modes were observed in each complex and all were blue shifted with respect to the free base.From the calculations, the unpaired electron was found to be contained in a ? antibonding orbital which is in the plane of the NO- HF and ONO-HF complexes.
- Davis, Steven R.,Andrews, Lester,Trindle, Carl O.
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- Etching silicon with HF-HNO3-H2SO4/H 2O mixtures- unprecedented formation of trifluorosilane, hexafluorodisiloxane, and Si-F surface groups
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The etching behaviour of sulfuric-acid-containing HF-HNO3 solutions towards crystalline silicon surfaces has been studied over a wide range of H2SO4 concentrations. For mixtures with low sulfuric acid concentration, NO2/N2O4, N 2O3, NO and N2O have been detected by means of FTIR spectroscopy. Increasing concentrations of nitric acid lead to high etching rates and to an enhanced formation of NO2/N2O 4. Different products were observed for the etching of silicon with sulfuric-acid-rich mixtures [c(H2SO4) > 13 mol L -1]. Trifluorosilane and hexafluorodisiloxane were identified by FTIR spectroscopy as additional reaction products. In contrast to the commonly accepted wet chemical etching mechanism, the formation of trifluorosilane is not accompanied by the formation of molecular hydrogen (according to Raman spectroscopy). Thermodynamic calculations and direct reactions of F 3SiH with the etching solution support an intermediate oxidation of trifluorosilane and the formation of hexafluorodisiloxane. The etched silicon surfaces were investigated by diffuse reflection FTIR and X-ray photoelectron spectroscopy (XPS). Surprisingly, no SiH terminations were observed after etching in sulfuric-acid-rich mixtures. Instead, a fluorine-terminated surface was found.
- Lippold, Marcus,Boehme, Uwe,Gondek, Christoph,Kronstein, Martin,Patzig-Klein, Sebastian,Weser, Martin,Kroke, Edwin
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p. 5714 - 5721
(2013/02/25)
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- Electron irradiation of solid nitrous oxide
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We report the results of chemical processing induced by 1 keV electron irradiation of a solid N2O ice sample formed at 25 K. Ozone and several oxides of nitrogen (NO2, N2O2, N2O3, N2O4 and N2O5) were observed to form during the irradiation period. Such reactions have important implications for the ice chemistry of outer solar system planets/satellites and interstellar ices.
- Sivaraman,Ptasinska,Jheeta,Mason
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p. 108 - 111
(2009/02/04)
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- Crystal Structure of Beryllium Nitrate Complexes (NO)2[Be(NO3)4] and Be4O(NO3)6
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Dinitrosonium tetranitratoberyllate (NO)2[Be(NO3)4] (I) was prepared by the reaction of BeCl2 with liquid N2O4 in the presence of ethyl acetate. The crystal structure of I is orthorhombic: a = 13.471(4) ?, b = 23.910(6) ?, c = 6.229(2) ?, Z= 8, space group Fdd2, R1, = 0.0412. The structure is built from nitrosonium cations (N-O 0.916(9) ?) and [Be(NO3)4]2- anions with tetrahedral coordination of Be (the Be-O distances are 1.627-1.641(9) ?) and monodentate nitrato groups. The thermal decomposition of I yields trigonal modification of beryllium oxonitrate, Be4O(NO3)6 (II): a = 13.638(3) ?, c = 6.475(2) ?, Z = 3, space group P3, R1 = 0.0585. The structure of II is built of tetranuclear Be4O(NO3)6 molecules with the tetracoordinated central O atom (Be-O 1.59-1.64 ?), forming the OBe4 tetrahedron, and six bidentate NO3 groups coordinated to each of the Be?Be edges with the Be-O distances of 1.60-1.72 ?. It seems that O is a high-temperature modification of beryllium oxonitrate.
- Troyanov,Tikhomirov,Znamenkov,Morozov
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p. 1791 - 1798
(2008/10/08)
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- A study of the heterogeneous reaction between dinitrogen pentaoxide and chloride ions on low-temperature thin films
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When low-temperature thin films of either ionic or covalent dinitrogen pentaoxide, N2O5, are exposed to gaseous HCl and water, the only products observed in the solid phase by reflection - absorption infrared spectroscopy (RAIRS) are molecular nitric acid and the oxonium ion. Nitryl chloride, ClNO2, is not detectable. When dinitrogen pentaoxide is co-deposited with hydrogen chloride and water at 85 K and annealed to 140 K, the resultant RAIR spectra indicate that the film is composed of H3O+Cl-, N2O5, HNO3, and D2h-N2O4. When nitryl chloride is co-deposited with either water or HCl/water mixtures, infrared spectra indicative of solid D2h-N2O4 are measured, as well as peaks corresponding to nitrate ions and cis-ClONO (chlorine nitrite). Reaction between ClNO2 and its isomer, cis-ClONO, is proposed as an explanation for the formation of dinitrogen tetraoxide in both systems. The proposed reaction mechanism for this hydrolysis is extended to the N2O5/H2O/HCl deposits in order to explain the lack of observable ClNO2 in such thin films.
- Sodeau, John R.,Roddis, Tristan B.,Gane, Matt P.
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p. 1890 - 1897
(2007/10/03)
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- Enhancement of N2O4 on Porous Glass at Room Temperature: A Key Intermediate in the Heterogeneous Hydrolysis of NO2?
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The heterogeneous hydrolysis of NO2 at surfaces in the atmosphere is believed to be a significant source of HONO, a key OH precursor in urban areas. However, the mechanism of this reaction is not known. The uptake of 2.9 Torr of NO2 in N2 at a total pressure of 508 Torr on a porous glass surface with varying amounts of surface-adsorbed water was studied using FTIR at 294 K. The ratio of N2O4 to NO2 was enhanced on the glass surface relative to the gas phase. On a relatively dry surface, the formation of surface-adsorbed HNO3 was observed over a period of ca. 20 h, likely due to the reaction with small amounts of water on the surface. Gas-phase NO and N2O were also generated. When larger amounts of water were initially present on the surface, surface-adsorbed HNO3 was formed immediately, as well as gas-phase NO, N2O, and HONO. Although the NO2 concentrations used in the present studies are much larger than those found in the atmosphere, this work suggests that N2O4 should be considered as a key intermediate in the heterogeneous hydrolysis of NO2 to form HONO.
- Barney, W. S.,Finlayson-Pitts, B. J.
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p. 171 - 175
(2007/10/03)
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- On the behaviour of nitrogen oxides in liquefied argon and krypton. Dimerisation of nitric oxide
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Solutions containing several nitrogen oxide species have been investigated in liquefied argon in the temperature range 84-105 K, and in liquefied krypton in the temperature range 116-150 K, using infrared spectroscopy.The following nitrogen oxide species were characterised in these solutions: NO, cis-ONNO, trans-ONNO, the asymmetric dimer ONON, asymmetric ONNO2, symmetric ONONO and N2O4 with D2h symmetry.The enthalpy of dimerisation of NO to cis-ONNO has been determined in liquefied argon to be -14.3 +/- 1 kJ mol-1.
- Sluyts, E. J.,Veken, B. J. Van der
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p. 249 - 268
(2007/10/02)
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- Electrochemical and Thermodynamic Properties of Oxygenated Nitrogen Compounds and Aromatics in Nitromethane. Application to the Energetic Aspects of the Nitration Process via Inner-sphere and/or Outer-sphere Electron-transfer Mechanisms
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The electrochemical and thermodynamic behaviour of oxygenated nitrogen compounds and aromatics has been studied in nitromethane (under weak solvation conditions) in order to provide energetic and mechanistic information concerning aromatic nitration compa
- Boughriet, Abdel,Wartel, Michel
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p. 809 - 810
(2007/10/02)
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- Fluorine-oxygen exchange reactions in IF5, IF7, and IF5O
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When reacted with alkali-metal nitrates, IF5 readily exchanges two fluorine ligands for a doubly bonded oxygen atom. In all cases MIF4O salts (M = Li, K, Cs) and FNO2 are formed as the primary products. The FNO2 byproduct undergoes a fast secondary reaction with MNO3 to yield equimolar amounts of N2O5 and MF. The N2O5 decomposes to N2O4 and 0.5 mol of O2, while the MF, depending on the nature of M, does or does not undergo complexation with the excess of IF5. Pure MIF4O salts, free of MF or MF·nIF5 byproducts, were prepared from MF, I2O5, and IF5 in either CH3CN or IF5 as a solvent. The new compounds LiIF4O, NaIF4O, RbIF4O, and NOIF4O were characterized by vibrational spectroscopy. It was also shown that, contrary to a previous report, FNO2 does not form a stable adduct with IF5 at temperatures as low as -78°C. An excess of IF7 reacts with MNO3 (M = Li, Na) to give MF, FNO2, IF5, and 0.5 mol of O2, but surprisingly no IF5O. With CsNO3, the reaction products are analogous, except for the CsF reacting with both the IF5 product and the excess of IF7 to give CsIF6·2IF5 and CsIF8, respectively. When in the IF7 reaction an excess of LiNO3, is used, the IF5 product undergoes further reaction with LiNO3, as described above. The IF5O molecule was found to be rather unreactive. It does not react with either LiF or CsF at 25 or 60°C or with LiNO3 or CsNO3 at 25°C. At 60°C with LiNO3, it slowly loses oxygen, with the IF5 product reacting to yield LiIF4O, as described above.
- Christe, Karl O.,Wilson, William W.,Wilson, Richard D.
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p. 904 - 908
(2008/10/08)
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- Reaction of certain nitrogen oxides with iron(III) porphyrin μ-oxo complexes
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The nitrogen oxides NO, N2O4, and N2O3 and the μ-oxo complexes [Fe(TPP)]2O and [Fe(OEP)]2O, where TPP and OEP are the dianions of meso-tetraphenylporphine and octaethylporphyrin, respectively, were reacted in toluene in the absence of O2. [Fe(TPP)]2O was reacted with the nitrogen oxides in dimethylacetamide (DMA). All of the reactions were followed by changes in the electronic spectra. The NO reaction with [Fe(TPP)]2O in toluene yielded a solid product, Fe(TPP)(NO)(NO2)·C7H8·2H 2O. The N2O4 and the N2O3 reactions in toluene produced Fe(TPP)NO3 and Fe(OEP)NO3, while in DMA these reactions gave an equilibrium amount of Fe(TPP)(DMA)x+, the solvated complex.
- Settin, Marc F.,Fanning, James C.
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p. 1431 - 1435
(2008/10/08)
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- Temperature Dependence of the Dissociation and of the Enthalpy of Formation of Mn(NO3)2N2O4
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The equilibrium pressure of the dissociation of Mn(NO3)2*N2O4(s) into Mn(NO3)2(s) and (N2O4, NO2)(g) at 275-318 K has been studied by a static membrane method.From the results the enthalpy (44.3 +/- 0.4 kJ mole-1), entropy (132 +/- 2 J mole-1 K-1), and Gibbs free energy (4.82 +/- 0.08 kJ mole-1) of the reaction Mn(NO3)2*N2O4(s) = N2O4(g) + Mn(NO3)2(s) have been calculated.
- Ukraintseva, E. A.,Natsina, A. A.,Yakovlev, I. I.
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p. 402 - 403
(2007/10/02)
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- A Study of the Gas-Phase Reaction of NO2 with O3 by Matrix Isolation Infrared Spectroscopy
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The observed products of the NO2 + O3 reaction are N2O3 and N2O4.The presence of N2O3 as a product indicates that NO is formed in secondary reactions and subsequently reacts with NO2 to produce N2O3.In the experiments where ozone was allowed to deposit at a rapid rate (0.27 mmol/h), infrared absorptions attributable to N2O5 and NO were observed.We attribute the production of N2O5 to the formation of the symmetrical NO3 radical.Our data indicate that both the symmetrical and asymmetrical NO3 radicals are intermediates in the reaction of NO2 + O3.An explanation for the presence of NO in nighttime chemistry is given.Attempts to isolate symmetrical NO3 were unsuccessful.
- Morris, V. R.,Bhatia, S. C.,Hall, John H.
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p. 3359 - 3361
(2007/10/02)
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- Disproportionation of Nitric Oxide at High Pressure
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A facile pressure-induced disproportionation of nitric oxide occurs at 176 K and 1.5 GPa.The reaction products are N2O4, N2O, and a small, variable amount of N2O3 as identified by infrared, Raman, and visible absorption spectroscopies.No free NO, N2O2, or NO2 is observed after warming the sample to room temperature.The N2O4 product subsequently photolyzes to form N2O3 and NO2+NO3-, and evidence for the nitrite form of N2O4 is reported.The N2O product is stable, once formed, to 14.0 GPa.
- Agnew, S. F.,Swanson, B. I.,Jones, L. H.,Mills, R. L.
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p. 1678 - 1682
(2007/10/02)
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- Comportement electrochimique du nitrite et de l'acide nitreux dans le sulfolane
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The electrochemical oxidation of nitrite dissolved in anhydrous and deoxygenated sulfolane has been studied by means of the platinum rotating disk electrode and cyclic voltammetry.The nitrite ion undergoes two consecutive oxydation steps: 2 NO2(1-) NO + NO3(1-) + e(1-) : NO + NO3(1-) N2O4 +e(1-) .The reactions and are, respectively, reversible and quasi reversible charge transfers.An extensive study of the first anodic wave indicates that nitrogen dioxide and its dimer, dinitrogen tetroxide, occurs as intermediates according to: NO2(1-) NO2 + e(1-) ; NO2 1/2 N2O4 ; 1/2 N2O4 + NO2(1-) NO + NO3(1) .The kinetic constants are large and the sum + + gives the overall reaction .The normal potentials accounting for steps and and the equilibrium constant of the reaction were calculated.The mechanism of NO2(1-) oxidation is complicated by water at trace levels in sulfolane: the intermediate N2O4 formed by rection can disproportionate: N2O4 + H2O HNO2 + HNO3; and with excess N2O4: HNO2 + N2O4 N2O3 + HNO3.The species N2O3 and HNO2 (with nitrate) are electroactive: N2O3 NO + 1/2 N2O4 + e(1-) ; HNO2 + NO3(1-) HNO3 + 1/2 N2O4 + e(1-) .In this case, the voltammetric curves show tree consecutive oxidation steps.To elucidate this new mechanism, we have studied the electrochemical behaviour of nitrous acid with nitrate (reaction ).The results show that system is kinetically controlled, and becouse of the weak solubility of NO, nitrous acid is not stable in the presence of N2O4 and/or HNO3.
- Boughriet, A.,Fischer, J. C.,Leman, G.,Wartel, M.
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