Phosphorus oxides

The phosphorus oxides are a series of chemical compounds made up of phosphorus and oxygen. These contain a cage-like P ₄ O ₆ basic structure. This can be formally derived from the P ₄ tetrahedron, with all six PP bonds being replaced by angled POP bridges. By gradually oxidizing the phosphorus atoms or introducing additional PO double bonds, five different phosphorus oxides of the general formula P ₄ O _n (n = 6-10, 18) are obtained.

Phosphorus oxides

Surname	formula	Structural formula	CAS number	molar mass	Molecular symmetry	Melting point	Remarks
Tetraphosphorus hexoxide, phosphorus trioxide, phosphorus (III) oxide	P 4 O 6		12440-00-5	219.89 g mol −1	T d	24 ° C	waxy, white crystals
Tetraphosphorheptoxide	P 4 O 7			235.89 g mol −1	C 3v
Tetraphosphorooctoxide Diphosphorus tetraoxide	P 4 O 8		70983-17-4	251.92 g mol −1	C 2v	> 100 ° C
Tetraphosphoronic oxide	P 4 O 9		12037-11-5	267.89 g mol −1	C 3v
Tetraphosphorus decaoxide phosphorus pentoxide phosphorus (V) oxide	P 4 O 10		16752-60-6	283.92 g mol −1	T d	359.9 ° C (sublimation)	colorless crystals

The reaction of tetraphosphorus hexoxide with ozone at low temperatures results in an unstable tetraozonide P ₄ O ₁₈ .

${\displaystyle \mathrm {P_{4}O_{6}+4\,O_{3}\rightarrow P_{4}O_{18}} }$

There are still phosphorus oxides that cannot be isolated but are only detectable in a gaseous state at high temperatures or very low pressure. By quenching a P ₄ containing O, and argon gas is obtained in addition to P ₄ O a mixture of PO, P ₂ O and PO ₂ . The phosphorus monoxide PO is probably the most abundant phosphorus-containing molecule in interstellar clouds . Some metal complexes are known of this compound.

Individual evidence

1. ^ ^{A b} Nils Wiberg, Egon Wiberg, Arnold Frederik Hollemann: Inorganische Chemie . Volume 1: Basics and main group elements. 103rd edition. De Gruyter, Berlin, Boston 2017, ISBN 978-3-11-051854-2 , pp. 783 ff . (accessed via De Gruyter Online)
2. ↑ ^{a b c} Entry on phosphorus oxides. In: Römpp Online . Georg Thieme Verlag, accessed on May 8, 2017.
3. ↑ ^{a b} R. Steudel : chemistry of non-metals, syntheses - structures - bonds - use. 4th edition. Walter de Gruyter, Berlin / Boston 2014, ISBN 978-3-11-030439-8 , pp. 406-409, (accessed from De Gruyter Online).
4. ↑ A. Dimitrov, B. Ziemer, W.-D. Hunnius, M. Meisel: The first ozonide of a phosphorus oxide - synthesis, characterization and crystal structure of P ₄ O ₁₈ . In: Angew. Chem. 115, 2003, pp. 2588-2590, doi: 10.1002 / anie.200351135 .
5. ↑ How the life element phosphorus came to earth. Wissenschaft.de - Martin Vieweg, January 16, 2020, accessed on January 17, 2020 .