Paramagnetism nitrogen dioxide

This chapter is devoted to a consideration of the results obtained in studies of the interactions of nitrogen oxides with polymers. There are eight nitrogen oxides, but only NO, NO2 and N-,04 are actually important as pollutants. Nitric oxide (NO) exists as a free radical, but it is reasonably stable in reactions with organic compounds. The paramagnetic nitrogen dioxide (NO2) is more active compared with NO. This gas is universally present in equilibrium with its dimer molecule ... 

The structure of nitrogen dioxide contains an unpaired (odd) electron and the molecule is consequently paramagnetic. The odd electron is not localised on any atom and the structure can be best represented as a resonance hybrid of the structures ... 

Gaseous nitrogen dioxide is a brown, paramagnetic, non-flammable, toxic, strongly oxidizing, coiTosive substance shipped in approved, low-pressure steel cylinders. It is prepared in situ by heating lead nitrate ... 

The Lewis structures of the oxides of nitrogen are shown in Figure 21.6. Two of these species, NO and NO are paramagnetic, with one impaired electron. When nitrogen dioxide is cooled, it dimerizes the unpaired electrons combine to form a single bond between the two nitrogen atoms ... 

Nitrogen dioxide (NO2), which is also an odd-electron molecule, has a V-shaped structure. The reddish brown, paramagnetic NO2 molecule readily dimerizes to form dinitrogen tetroxide,... 

NO2 Nitrogen dioxide 134° Brown, paramagnetic gas exists in equilibrium with N204 2N02 N2O4... 

The nitrogen dioxide molecule has 17 valency electrons, and its physical properties are consistent with those expected for an odd-electron molecule. It is paramagnetic, and a volume susceptibility of 3 X c.g.s. unit (39) agrees... 

Metal- and proton-exchanged zeolites have been recently attracted much attention because of their selective catalytic activity to efficiently reduce nitrogen monoxide (NO) by hydrocarbon in an 02-rich atmosphere [1]. The formation of nitrogen dioxide (NO2) from NO and O2 has been suggested as an important step in the selective reduction [2, 3] NO2 is one of rare stable paramagnetic gaseous molecules and has been subjected to electron spin resonance (ESR) studies [4-7]. The ESR parameters and their relation/to the electronic structure have been well established [4] and NO2 can be used as a "spin probe" for the study of molecular dynamics at the gas-solid interface by ESR. 

Nitrogen dioxide is a choking, poisonous, brown gas that contributes to the color and odor of smog. The oxidation number of nitrogen in NO2 is-1-4. NO2, like NO, is paramagnetic. It disproportionates in water to form nitric acid and nitrogen oxide ... 

Nitrogen dioxide is paramagnetic. It has a strong tendency to dimerize to dinitrogen tetroxide, which is a diamagnetic molecule ... 

Host-guest complexes formed upon reversible reaction between NO2 and simple calix[4]arenes were also studied (72). Nitrogen dioxide (NO2) is a paramagnetic gas of an intense brown-orange color. It exists in equilibrium... 

NO is one of the simplest odd-electron species in which the presence of an unpaired electron reduces the bond order to 2.5 (whereas it is around 3 in NO ). Due to these chemical properties, NO is reluctant to dimerize, has paramagnetic properties, and reacts with atoms and free radicals. In the gaseous phase NO reacts with oxygen to form nitrogen dioxide (NO2), while in the aqueous phase NO reacts with oxygen to form nitrite. In vivo, nitrite reacts with oxyhemoglobin, resulting in the formation of its stable metabo-... 

CHEMICAL PROPERTIES nonflammable gas contains odd number of electrons and is paramagnetic combines with oxygen to form nitrogen dioxide (NO2), a brown gas combines with chlorine and bromine to form the nitrosyl halides, such as nitrosyl chloride (NOCl) reacts with water to form nitric acid rapidly converted in air to nitrogen dioxide reacts with boron, carbon disulfide, chlorine monoxide, chromium, fluorine, fuels, uranium hydrocarbons, nitrogen trichloride, and phosphine FP (NA) LFL/UFL (NA) AT (NA) HF (-21.5 kcal/mole at 18°C) HK 2.3 kJ/mol at 109.5 K). 

The interaction of nitric oxide (NO) with metal ions in zeolites has been one of the major subjects in catalysis and environmental science and the first topic was concerned with NO adsorbed on zeolites. NO is an odd-electron molecule with one unpaired electron and can be used here as a paramagnetic probe to characterize the catalytic activity. In the first topic focus was on a mono NO-Na" complex formed in a Na -LTA type zeolite. The experimental ESR spectrum was characterized by a large -tensor anisotropy. By means of multi-frequency ESR spectroscopies the g tensor components could be well resolved. The N and Na hyperfine tensor components were accurately evaluated by ENDOR spectroscopy. Based on these experimentally obtained ESR parameters the electronic and geometrical structures of the NO-Na complex were discussed. In addition to the mono NO-Na complex the triplet state (NO)2 bi-radical is formed in the zeolite and dominates the ESR spectrum at higher NO concentration. The structure of the bi-radicai was discussed based on the ESR parameters derived from the X- and Q-band spectra. Furthermore the dynamical ESR studies on nitrogen dioxides (NO2) on various zeolites were briefly presented. 

The mixture is a pungent brownish liquid that boils at 2UC. Lower temperatures and increasing pressure shift the reaction to the production of nitrogen tetroxide. Nitrogen dioxide is a brown paramagnetic species while the dimer is colorless and diamagnetic at 21°C the equilibrium mixture contains 0.08% NOg. 

NO2 Nitrogen dioxide a Paramagnetic, odd-electron species brown gas serious air pollutant... 

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