Rhodium(IV) oxide

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Rhodium(IV) oxide
RhO2structure.png
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.032.021 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 235-237-0
PubChem CID
  • InChI=1S/2O.Rh/q2*-2;+4 Yes check.svgY
    Key: ZLDSZHMBHVKLCB-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/2O.Rh/q2*-2;+4
    Key: ZLDSZHMBHVKLCB-UHFFFAOYAD
  • [Rh+4].[O-2].[O-2]
Properties
RhO2
Molar mass 134.904 g/mol
Appearanceblack crystalline solid
Density 7.2 g/cm3
Melting point 1,050 °C (1,920 °F; 1,320 K)(decomposes)
Solubility insoluble in aqua regia
Structure
tetragonal (rutile)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Rhodium(IV) oxide (or rhodium dioxide) is the chemical compound with the formula Rh O2.

Contents

Chemical properties

RhO2 is highly insoluble even in hot aqua regia. [1]

Structure

RhO2 has the tetragonal rutile structure. [2]

Physical properties

RhO2 has metallic resistivity with values <10−4 Ohm·cm. It transforms in air to Rh2O3 at 850 °C and then to metal and oxygen at 1050 °C. [2]

See also

Related Research Articles

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3
CO
2
). This dark green powder is slightly soluble in polar solvents, including water. It is used as a catalyst for cyclopropanation of alkenes. It is a widely studied example of a transition metal carboxylate complex.

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References

  1. O. Muller and R. Roy (1968). "Formation and stability of the platinum and rhodium oxides at high oxygen pressures and the structures of Pt3O4, β-PtO2 and RhO2". Journal of the Less Common Metals. 16 (2): 129–146. doi:10.1016/0022-5088(68)90070-2.
  2. 1 2 R. D. Shannon (1968). "Synthesis and properties of two new members of the rutile family RhO2 and PtO2". Solid State Communications. 6 (3): 139–143. Bibcode:1968SSCom...6..139S. doi:10.1016/0038-1098(68)90019-7.