Protactinium tetrafluoride
Appearance
	
	
| Identifiers | |
|---|---|
3D model (JSmol) 
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|
  | |
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| Properties | |
| F4Pa | |
| Molar mass | 307.02949 g·mol−1 | 
| Appearance | dark brown crystals | 
| Related compounds | |
Related compounds 
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Uranium tetrafluoride, neptunium tetrafluoride, plutonium tetrafluoride | 
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). 
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Protactinium tetrafluoride is a binary inorganic compound of protactinium metal and fluorine with the chemical formula PaF4.[1]
Synthesis
[edit]Protactinium tetrafluoride can be obtained by fluorinating protactinium(IV) oxide with a hydrogen fluoride / hydrogen mixture at 600 °C:
- PaO2 + 4HF → PaF4 + 2H2O
 
The effect of hydrogen fluoride and hydrogen on protactinium(V) oxide:
- Pa2O5 + 8HF + H2 → 2PaF4 + 5H2O
 
Physical properties
[edit]PaF4 forms dark brown, monoclinic, needlelike crystals of UF4 structure.[2][3] The cell parameters are: a = 1.27 nm, b = 1.07 nm, c = 0.842 nm, β = 126.3°.
The compound is soluble in aqueous ammonium fluoride solutions.[4]
Chemical properties
[edit]Protactinium tetrafluoride reacts with oxygen and fluorine:[2]
- 2PaF4 + F2 → 2PaF5
 
- 4PaF4 + O2 → 2Pa2OF8
 
The compound reacts with alkalis:
- PaF4 + 4NaOH → PaO2 + 4NaF + 2H2O
 
The metal is displaced from the salt by barium:
- PaF4 + 2Ba → Pa + 2BaF2
 
References
[edit]- ^ Hawkins, Donald T. (6 December 2012). Binary Fluorides: Free Molecular Structures and Force Fields A Bibliography (1957–1975). Springer Science & Business Media. p. 50. ISBN 978-1-4684-6147-3. Retrieved 2 April 2024.
 - ^ a b Proceedings of the Protactinium Chemistry Symposium: Gatlinburg, Tennessee, April 25-26, 1963 : Sessions 1-111. United States Atomic Energy Commission, Technical Information Service Extension. 1964. p. 57. Retrieved 2 April 2024.
 - ^ Advances in Inorganic Chemistry and Radiochemistry. Academic Press. 28 February 1970. p. 7. ISBN 978-0-08-057861-3. Retrieved 2 April 2024.
 - ^ Advances in Inorganic Chemistry and Radiochemistry. Academic Press. 28 February 1970. p. 9. ISBN 978-0-08-057861-3. Retrieved 2 April 2024.
 
