Promethium(III) oxide

Cubic

A = 1099 pm

Coral- red solid (C- type)

Fixed

6.85 g · cm -3

2130 ° C

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Promethium (III ) oxide ( Pm2O3 ), the oxide of the rare earth metal is promethium.

Representation

Promethium (III ) oxide of promethium (III ) oxalate is represented by annealing at 800 ° C.

Properties

It comes in three modifications before (A -, B-, and C- type). The A- type has a hexagonal crystal lattice (purple brown), the B- type (violet pink ) is a monoclinic distortion of the A- type and C- type has an isomorphic cubic manganese (III ) oxide structure ( coral ). At room temperature it crystallizes in the C- type, the other two structures are stable only at higher temperatures.

When heated to 750-800 ° C to convert the cubic to the monoclinic form, this transformation can be reversed only by melting of the oxide. The transformation from the monoclinic to the hexagonal form occurs at 1740 ° C. The melting point is 2130 ° C.

The specific magnetic susceptibility is 15.5 · 10-6 cm3 / g, a molar magnetic susceptibility of χmol 2660 · 10-6 cm3 / g

Safety

Classifications according to the Hazardous Substances Ordinance are not available because they only include the chemical danger and play a very minor role compared to the risks based on the radioactivity. Even the latter applies only if there is a relevant material for this amount.