Neptunium tetrachloride is a binary inorganic compound of neptunium metal and chlorine with the chemical formula NpCl4.[1][2]
Synthesis
The compound can be prepared by:
- the reaction of neptunium nitride with HCl:[3]
- 2 NpN + 8 HCl → N2 + 4 H2 + 2 NpCl4
- the reaction of neptunium sulfide with HCl:
- Np2S3 + 8 HCl → 2 NpCl4 + 3 H2S + H2
- the reaction of carbon tetrachloride with neptunium(IV) oxide or NpO2. Neptunium tetrachloride is formed as a yellow sublimate.[4]
- NpO2 + CCl4 → NpCl4 + CO2
Other reactions are also used.[5]
Physical properties
NpCl4 crystallizes in tetragonal crystal system of space group I4/amd.[6]
Chemical properties
The compound reacts with ammonia to produce neptunium trichloride:[3]
- 6 NpCl4 + 2 NH3 → 6 NpCl3 + 6 HCl + N2
Neptunium tetrachloride can be reduced to neptunium trichloride by hydrogen at 450 °C.
- 2 NpCl4 + H2 → 2 NpCl3 + 2HCl
NpCl4 can form Lewis base adducts with non-protic solvents such as 1,2-dimethoxyethane (DME), pyridine and acetonitrile. These compounds are more accessible in practice than the binary NpCl4 salt. Solvates of the general formula NpCl4Lx may thus be isolated.[7] The most commonly used starting material for metal-organic neptunium chemistry is NpCl4(DME)2, which can be isolated as a pink powder.[8]
References
- ^ "WebElements Periodic Table » Neptunium » neptunium tetrachloride". webelements.com. Retrieved 1 April 2024.
- ^ Stone, J. A.; Jones, E. R. (15 February 1971). "Mössbauer Spectra and Magnetic Susceptibility of Neptunium Tetrachloride below 85°K". The Journal of Chemical Physics. 54 (4): 1713–1718. Bibcode:1971JChPh..54.1713S. doi:10.1063/1.1675076. Retrieved 1 April 2024.
- ^ a b Sheft, Irving; Fried, Sherman (1950). New Neptunium Compounds. U.S. Atomic Energy Commission, Technical Information Division. p. 5. Retrieved 1 April 2024.
- ^ Fried, S. (1947). The Basic Dry Chemistry of Neptunium. Atomic Energy Commission. p. 1. Retrieved 1 April 2024.
- ^ Ahrland, S.; Bagnall, K. W.; Brown, D. (7 June 2016). The Chemistry of the Actinides: Comprehensive Inorganic Chemistry. Elsevier. p. 181. ISBN 978-1-4831-5934-8. Retrieved 1 April 2024.
- ^ Spirlet, Marie-Rose; Jemine, Xavier; Goffart, Jean (1 January 1995). "A single-crystal X-ray structure determination of neptunium tetrachloride". Journal of Alloys and Compounds. 216 (2): 269–271. doi:10.1016/0925-8388(94)01264-I. ISSN 0925-8388. Retrieved 1 April 2024.
- ^ Lopez, Lauren M.; Uible, Madeleine C.; Zeller, Matthias; Bart, Suzanne C. (2024-06-04). "Lewis base adducts of NpCl4". Chemical Communications. 60 (46): 5956–5959. doi:10.1039/D4CC01560F. ISSN 1364-548X. PMID 38766982.
- ^ Reilly, Sean D.; Brown, Jessie L.; Scott, Brian L.; Gaunt, Andrew J. (2013-12-18). "Synthesis and characterization of NpCl4(DME)2 and PuCl4(DME)2 neutral transuranic An(IV) starting materials". Dalton Transactions. 43 (4): 1498–1501. doi:10.1039/C3DT53058B. ISSN 1477-9234. PMID 24285347.