Promethium (III) fluoride

Crystal structure
	__ Pm 3+ __ F -
Crystal system	hexagonal
Space group	P 6 3 / mcm (No. 193)
Lattice parameters	a = 697 pm ; c = 719 pm
Coordination numbers	Pm [9], F [3]
General
Surname	Promethium (III) fluoride
other names	Promethium trifluoride
Ratio formula	PmF 3
Brief description	purple-pink salt
External identifiers / databases
Wikidata	Q1796798
properties
Molar mass	203.91 g mol −1 ( 147 μm)
Physical state	firmly
density	6.72 g cm −3
Melting point	1338 ° C
Hazard and safety information
	; Radioactive
GHS hazard labeling ; no classification available
GHS hazard labeling ; no classification available
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Promethium (III) fluoride is a chemical compound consisting of the elements promethium and fluorine . It has the formula PmF ₃ and belongs to the fluoride class of substances .

presentation

Promethium (III) fluoride is sparingly soluble in water; it is obtained from a Pm ³⁺ nitric acid solution by adding HF solution ; the precipitate has a pale pink color.

{\ displaystyle \ mathrm {Pm ^ {3 +} \ _ {(aq)} + \ 3 \ F ^ {-} \ _ {(aq)} \ longrightarrow \ PmF_ {3} \ _ {(s)} \ downarrow}}

properties

Crystalline anhydrous promethium (III) fluoride is a purple-pink salt with a melting point of 1338 ° C. It crystallizes in the hexagonal crystal system ( LaF ₃ -type ) with the lattice parameters a = 697 pm and c = 719 pm and a calculated density of 6.72 g cm ⁻³ .

If PmF ₃ · x H ₂ O is heated, promethium (III) oxyfluoride (PmOF), which is colored purple-pink, is formed.

1963 could Fritz Weigel first metallic promethium by heating promethium (III) fluoride with lithium in tantalum - crucible manufacture.

{\ displaystyle \ mathrm {PmF_ {3} \ + \ 3 \ Li \ \ longrightarrow \ Pm \ + \ 3 \ LiF}}

safety instructions

Classifications according to the CLP regulation are not available because these only include chemical hazard and play a completely subordinate role compared to the hazards based on radioactivity . The latter also only applies if the amount of substance involved is relevant.

literature

Fritz Weigel: The chemistry of promethium , in: Fortschr. Chem. Forsch. , 1969 , 12 (4), pp. 539-621 ( doi : 10.1007 / BFb0051097 ).
James E. Huheey: Inorganische Chemie , 1st edition, de Gruyter, Berlin 1988, ISBN 3-11-008163-6 , pp. 873-900.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g Weigel: Die Chemie des Promethiums , pp. 587-588.
^ ^A ^b A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 1942.
↑ The hazards emanating from radioactivity do not belong to the properties to be classified according to the GHS labeling. With regard to other hazards, this substance has either not yet been classified or a reliable and citable source has not yet been found.
↑ Gmelin's Handbook of Inorganic Chemistry , System No. 39, Part C 3, pp. 194-195.
^ Fritz Weigel: Representation of metallic promethium , in: Angewandte Chemie , 1963 , 75 (10), pp. 451–451 ( doi : 10.1002 / anie.19630751009 ).

[Weigel_587_588-1] ↑ ^a ^b ^c ^d ^e ^f ^g Weigel: Die Chemie des Promethiums , pp. 587-588.

[HOWI_1942-2] A ^b A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 1942.

[NV-3] The hazards emanating from radioactivity do not belong to the properties to be classified according to the GHS labeling. With regard to other hazards, this substance has either not yet been classified or a reliable and citable source has not yet been found.

[4] Gmelin's Handbook of Inorganic Chemistry , System No. 39, Part C 3, pp. 194-195.

[PM_METALL-5] Fritz Weigel: Representation of metallic promethium , in: Angewandte Chemie , 1963 , 75 (10), pp. 451–451 ( doi : 10.1002 / anie.19630751009 ).