Trioxide

A trioxide is a compound with three oxygen atoms. For metals with the M₂O₃ formula there are several common structures. Al₂O₃, Cr₂O₃, Fe₂O₃, and V₂O₃ adopt the corundum structure. Many rare earth oxides adopt the "A-type rare earth structure" which is hexagonal. Several others plus indium oxide adopt the "C-type rare earth structure", also called "bixbyite", which is cubic and related to the fluorite structure.^[1]

^ Jaffe, Howard W. (1996). Crystal Chemistry and Refractivity. Courier Dover Publications. pp. 266–272. ISBN 978-0-486-69173-2. Archived from the original on 2023-09-08. Retrieved 2021-12-05.

[Jaffe-1] Jaffe, Howard W. (1996). Crystal Chemistry and Refractivity. Courier Dover Publications. pp. 266–272. ISBN 978-0-486-69173-2. Archived from the original on 2023-09-08. Retrieved 2021-12-05.

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