Terbium(III) oxide

Terbium(III) oxide, also known as terbium sesquioxide, is a sesquioxide of the rare earth metal terbium, having chemical formula Tb
₂O
₃. It is a p-type semiconductor when doped with calcium,[3] and may be prepared by the reduction of Tb
₄O
₇ in hydrogen at 1300 °C for 24 hours.[4]

Terbium(III) oxide

Names
IUPAC name terbium(III) oxide
Other names terbium trioxide, terbia, terbium sesquioxide
Identifiers
CAS Number	12036-41-8^Y
3D model (JSmol)	Interactive image
ECHA InfoCard	100.031.668
EC Number	234-849-5
PubChem CID	159410
CompTox Dashboard (EPA)	DTXSID40276469
InChI InChI=1/3O.2Tb/q3*-2;2*+3
SMILES [O-2].[O-2].[O-2].[Tb+3].[Tb+3]
Properties
Chemical formula	O3Tb2
Molar mass	365.848 g·mol^−1
Appearance	white crystals
Density	7.91 g/cm^3
Melting point	2,410 °C (4,370 °F; 2,680 K)
Magnetic susceptibility (χ)	0.07834 cm^3/mol
Structure
Crystal structure	Cubic, cI80
Space group	Ia-3, No. 206[1]
Thermochemistry
Std molar entropy (S^o298)	156.90 J/mol·K [2]
Std enthalpy of formation (ΔfH^⦵298)	-1865.23 kJ/mol [2]
Gibbs free energy (ΔfG˚)	-1776.553 kJ/mol [2]
Hazards
EU classification (DSD) (outdated)	not listed
Related compounds
Other anions	Terbium(III) chloride
Other cations	Gadolinium(III) oxide Dysprosium(III) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is ^YN ?)
Infobox references

Tb₄O₇+H₂->2 Tb₂O₃+H₂O

It is a p-type semiconductor.[5]

It is a basic oxide and easily dissolved to dilute acids, and then almost colourless terbium salt is formed.

Tb₂O₃ + 6 H⁺ → 2 Tb³⁺ + 3 H₂O

The crystal structure is cubic and the lattice constant is a = 1057 pm.[6]

References

1. Curzon A.E.; Chlebek H.G. (1973). "The observation of face centred cubic Gd, Tb, Dy, Ho, Er and Tm in the form of thin films and their oxidation". J. Phys. F. 3 (1): 1–5. doi:10.1088/0305-4608/3/1/009.
2. R. Robie, B. Hemingway, and J. Fisher, “Thermodynamic Properties of Minerals and Related Substances at 298.15K and 1bar Pressure and at Higher Temperatures,” US Geol. Surv., vol. 1452, 1978.
3. Reidar Haugsrud; Yngve Larring & Truls Norby (December 2005). "Proton conductivity of Ca-doped Tb
   ₂O
   ₃". Solid State Ionics. Elsevier B.V. 176 (39–40): 2957–2961. doi:10.1016/j.ssi.2005.09.030.
4. G. J. McCarthy (October 1971). "Crystal data on C-type terbium sesquioxide (Tb
   ₂O
   ₃)". Journal of Applied Crystallography. 4 (5): 399–400. doi:10.1107/S0021889871007295.
5. Reidar Haugsrud; Yngve Larring & Truls Norby (December 2005). "Proton conductivity of Ca-doped Tb₂O₃". Solid State Ionics. Elsevier B.V. 176 (39–40): 2957–2961. doi:10.1016/j.ssi.2005.09.030.
6. N. C. Baenzinger, H. A. Eick, H. S. Schuldt, L. Eyring: Terbium Oxides. III. X-Ray Diffraction Studies of Several Stable Phases. In: Journal of the American Chemical Society, 1961, 83, 10, S. 2219-23.