Californium(III) oxide

Californium(III) oxide is a binary inorganic compound of californium and oxygen with the formula Cf
₂O
₃.^[1] It is one of the first obtained solid compounds of californium, synthesized in 1958.

Californium(III) oxide

Names
Other names Californium sesquioxide, dicalifornium trioxide
Identifiers
CAS Number	12050-91-8
3D model (JSmol)	Interactive image
InChI InChI=1S/2Cf.3O/q2*+3;3*-2 Key: BZGNRENQZZWCKH-UHFFFAOYSA-N
SMILES [Cf+3].[Cf+3].[O-2].[O-2].[O-2]
Properties
Chemical formula	Cf2O3
Molar mass	550 g·mol−1
Appearance	yellow-green solid
Density	g/cm3
Melting point	1,750 °C (3,180 °F; 2,020 K)
Solubility in water	insoluble
Structure
Crystal structure	orthorhombic
Related compounds
Related compounds	Californium dioxide
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	radioactive
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

The compound can be prepared by burning ionite in air, on which ions of trivalent californium are sorbed, at a temperature of 1400 °C. It can also be obtained by β-decay of berkelium(III) oxide.^{[citation needed]}

Physical properties

Californium(III) oxide forms a yellow-green solid with a melting point of 1750 °C and exists in three modifications.^[2] The body-centered cubic modification forms a crystal lattice with a = 1083.9 ± 0.4 pm. The transition temperature between body-centered cubic and monoclinic structures is about 1400 °C.^[3][4]

It is insoluble in water.^[5]

References

1. Morss, Lester R.; Fuger, J.; Goffart, J.; Edelstein, N.; Shalimoff, G. V. (1 January 1987). "Enthalpy of formation and magnetic susceptibility of californium sesquioxide, Cf2O3". Journal of the Less Common Metals. 127: 251–257. doi:10.1016/0022-5088(87)90385-7. ISSN 0022-5088. Retrieved 10 April 2023.
2. Macintyre, Jane E. (23 July 1992). Dictionary of Inorganic Compounds. CRC Press. p. 2826. ISBN 978-0-412-30120-9. Retrieved 10 April 2023.
3. Copeland, J. C.; Cunningham, B. B. (1 March 1969). "Crystallography of the compounds of californium—II crystal structure and lattice parameters of californium oxychloride and californium sesquioxide". Journal of Inorganic and Nuclear Chemistry. 31 (3): 733–740. doi:10.1016/0022-1902(69)80020-5. ISSN 0022-1902. Retrieved 10 April 2023.
4. Green, J. L.; Cunningham, B. B. (1 September 1967). "Crystallography of the compounds of californium. I. Crystal structure and lattice parameters of californium sesquioxide and californium trichloride". Inorganic and Nuclear Chemistry Letters. 3 (9): 343–349. doi:10.1016/0020-1650(67)80040-0. ISSN 0020-1650. Retrieved 10 April 2023.
5. Schweitzer, George K.; Pesterfield, Lester L. (14 January 2010). The Aqueous Chemistry of the Elements. Oxford University Press. p. 406. ISBN 978-0-19-539335-4. Retrieved 11 April 2023.