In 1997, Souter et al. reported the production of UH4 reacting laser ablated uranium atoms with dihydrogen and capturing the product on solid argon. The assignment of the structure was made using infrared spectroscopic evidence supported by DFT calculations. Uranium(IV) hydride has a quasi-tetrahedral (Cs) structure. UH4 is formed by the successive insertion of uranium into two hydrogen molecules:
U + H2 → UH2
UH2 + H2 → UH4
Further reaction with hydrogen, only produces dihydrogen complexes: UH4(H2)n (1 ≤ n ≤ 6).
^Souter, Philip F.; Kushto, Gary P.; Andrews, Lester; Neurock, Matthew (1997). "Experimental and Theoretical Evidence for the Formation of Several Uranium Hydride Molecules". Journal of the American Chemical Society. 119 (7): 1682–1687. doi:10.1021/ja9630809.
^Raab, Juraj; Lindh, Roland H.; Wang, Xuefeng; Andrews, Lester; Gagliardi, Laura (2007). "A Combined Experimental and Theoretical Study of Uranium Polyhydrides with New Evidence for the Large Complex UH4(H2)6". The Journal of Physical Chemistry A. 111 (28): 6383–6387. Bibcode:2007JPCA..111.6383R. doi:10.1021/jp0713007. PMID17530832.