Phosphorus dioxide

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Column 1	Column 2
IUPAC name
Phosphorus(IV) oxide
Other names
Phosphorus dioxide
CAS Number	.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}12164-97-5
3D model (JSmol)	Interactive image
ChEBI	CHEBI:37370
ChemSpider	122825
Gmelin Reference	1065
PubChem CID	139273
CompTox Dashboard (EPA)	DTXSID60153329
InChI
InChI=1S/O2P/c1-3-2Key: CJDZTJNITSFKRE-UHFFFAOYSA-N
SMILES
O=P[O]
Chemical formula	O2P
Molar mass	62.972 g·mol−1
Heat capacity (C)	39.5 joules (9.4 cal) per mole per K
Std molarentropy (S⦵298)	252.1 joules (60.3 cal) per mole per K
Std enthalpy offormation (ΔfH⦵298)	−279.9 joules (−66.9 cal) per mole
Gibbs free energy (ΔfG⦵)	−281.6 joules (−67.3 cal) per mole
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Infobox references | |

Phosphorus dioxide (.mw-parser-output .template-chem2-su{display:inline-block;font-size:80%;line-height:1;vertical-align:-0.35em}.mw-parser-output .template-chem2-su>span{display:block;text-align:left}.mw-parser-output sub.template-chem2-sub{font-size:80%;vertical-align:-0.35em}.mw-parser-output sup.template-chem2-sup{font-size:80%;vertical-align:0.65em}PO2) is a gaseous oxide of phosphorus. It is a free radical that plays a role in the chemiluminescence of phosphorus and phosphine. It is produced when phosphates are heated to high temperatures.

In the ground state the molecule is bent, like nitrogen dioxide, but there is an excited state that is linear.

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