Nitrogen (I) fluoride

Structural formula
General
Surname	Nitrogen (I) fluoride
other names	Dinitrogen difluoride Difluorodiazine
Molecular formula	N 2 F 2
Brief description	colorless gas
External identifiers / databases
CAS number 13812-43-6 ( cis isomer) 13776-62-0 ( trans isomer) PubChem 139594 ChemSpider 4516471 Wikidata Q412958
properties
Molar mass	66.01 g mol −1
Physical state	gaseous
density	4.6 g l −1 2.9 g l −1
Melting point	<−195 ° C ( cis isomer) −172 ° C ( trans isomer)
boiling point	−106 ° C ( cis isomer) −111 ° C ( trans isomer)
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Nitrogen (I) fluoride is a chemical compound consisting of the elements nitrogen and fluorine with the empirical formula N ₂ F ₂ and is one of the nitrogen halides . In the compound, nitrogen has the +1 oxidation state .

presentation

Nitrogen (I) fluoride can be obtained from the thermal decomposition of fluoroazide . Fluorazide decomposes to nitrogen (I) fluoride and molecular nitrogen.

${\displaystyle \mathrm {2\ N_{3}F\ {\xrightarrow {\Delta T}}\ \ 2\ N_{2}\ +\ N_{2}F_{2}} }$

Another synthetic route consists in the reaction of difluoramine with potassium fluoride .

${\displaystyle \mathrm {2\ HNF_{2}\ +\ 2\ KF\longrightarrow \ 2\ HNF_{2}\cdot KF} }$ ${\displaystyle \mathrm {\longrightarrow \ N_{2}F_{2}\ +\ 2\ KHF_{2}} }$

The reaction of sodium azide with fluorine , which also forms nitrogen (III) fluoride, is also possible.

${\displaystyle \mathrm {2\ NaN_{3}+2\ F_{2}\longrightarrow N_{2}F_{2}+2\ N_{2}+2\ NaF} }$

Alternatively, the representation takes place via photolysis of tetrafluorohydrazine with bromine :

${\displaystyle {\ce {N2F4 ->[hv][Br_2] N2F2 + Nebenprodukte}}}$

properties

Nitrogen (I) fluoride is a colorless gas at room temperature with an odor similar to that of nitrogen dioxide , which breaks down into the elements above 300 ° C. There are the cis - and the trans form as isomers , which together in thermodynamic equilibrium are. The cis form is the energetically more favorable isomer and is 90% present at 25 ° C. The compound reacts with fluorine to form nitrogen (III) fluoride. It is completely resistant to acidic and alkaline hydrolysis, but is broken down by acidic potassium iodide solution.

The distance between the two nitrogen atoms corresponds to that of a double bond (120.9  pm in the cis , 122.4 pm in the trans isomer). The NF bond length is 140.9 pm for the cis and 139.8 pm for the trans isomer, which corresponds to the expected bond length for a single bond.

Individual evidence

1. ↑ ^{a b c d e} A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 .
2. ↑ cis nitrogen (I) fluoride at webelements.com
3. ↑ trans nitrogen (I) fluoride at webelements.com
4. ↑ ^{a b c d e} Leon M. Zaborowski et al .: Chlorodifluoroamine and Difluorodiazene - B. Difluorodiazene (Dinitrogen difluoride) . In: Aaron Wold and John K. Ruff (Eds.): Inorganic Syntheses . tape 14 . McGraw-Hill Book Company, Inc., 1973, ISBN   07-071320-0  ( defective ) , p. 34-39 (English).
5. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
6. ↑ ^{a b c} Georg Brauer (ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , p. 200.