Nitrogen compounds spectroscopy

Electron diffraction studies have also provided structural information for chalcogen-nitrogen compounds that are liquids or gases at room temperature, e.g., the 1,2,3,5-dithiadiazolyl radical [CF3CNSSN] (3)22 and the 1,3,2-di-thiazolyl [CF3CSNSCCF3] (4).23 The structure of the trithiatriazine (NSF)3 (5) has also been determined in the gas phase by a combination of electron diffraction and microwave spectroscopy, which shows that all three fluorine atoms are axial.24... 

Analyzing and using spectroscopy to determine nitrogen compounds... 

Osaka etal. [172] have also studied the adsorption structures of acrylonitrile on Ag(lll) and Ag(llO) surfaces using IR reflection/absorption spectroscopy. Other nitrogen compounds are discussed in the section devoted to biochemically important compounds. 

PNMR spectroscopy and generates heterocycles that are hybrids of r-electron-rich (S-N) and tt-electron-precise ring systems (cyclophosphazenes, see Phosphorus-Nitrogen Compounds). 

The method is based on the ability of TCNQ to react with bonded nitrogen compounds (secondary, tertiary amines) to form stable ion-radical salts (IRS) under mild conditions and with high yields. Completeness of formation of stable IRS has been monitored by ESR and electronic spectroscopy. One of the most important features of this method is the formation of two-dimensional phase by TCNQ anion-radicals on the surface, if bonded donor molecules are fixed at a small distance between their anchoring points, i.e. when separation between points of fixation is in the range 1-1.5 nm. ESR spectra of such samples contain an exchange-narrowed singlet with AH = 0.5 — 1.1 Gs, and g-factor 2.0025. Such spectra are typical for crystalline samples of IRS of TCNQ [25]. If bonded donor molecules are separated by as much as 2 nm or more, a distinct phase of TCNQ IRS is not formed. ESR spectra of such samples reveal either dipole-dipole broadening or hyperfine structure. 

Identifying Nitrogen Compounds with Analysis and Spectroscopy.246... 

Nitrogen-14 spectroscopy can be very useful in deciding preferred tautomeric structures in nitrogen heterocyclic chemistry an example of this is found in the 2-substituted benzthiazoles, which can exist in two tautomeric forms (4) and (5). The 4- and 6-substituted derivatives exhibit chemical shifts in the range expected for aromatic compounds. 

Since Allen and Senoff prepared the first stable molecular nitrogen compounds, [Ru(N2)(NH3)5]X2 (X = Br, I", BFJ, etc.), a large number of molecular nitrogen compounds have been synthesized. The chemistry and spectroscopy of these compounds have been reviewed extensively. " The structures of molecular nitrogen compounds are classified into three types ... 

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