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PrH2 is Fluorite structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Pr is bonded in a body-centered cubic geometry to eight equivalent H atoms. All Pr–H bond lengths are 2.41 Å. H is bonded to four equivalent Pr atoms to form a mixture of edge and corner-sharing HPr4 tetrahedra.
HPr is Wurtzite structured and crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. Pr is bonded to four equivalent H atoms to form corner-sharing PrH4 tetrahedra. There are three shorter (2.35 Å) and one longer (2.41 Å) Pr–H bond lengths. H is bonded to four equivalent Pr atoms to form corner-sharing HPr4 tetrahedra.
PrH3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Pr3+ is bonded to twelve H1- atoms to form a mixture of distorted face, edge, and corner-sharing PrH12 cuboctahedra. There are eight shorter (2.38 Å) and four longer (2.62 Å) Pr–H bond lengths. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded to four equivalent Pr3+ atoms to form a mixture of edge and corner-sharing HPr4 tetrahedra. In the second H1- site, H1- is bonded in a square co-planar geometry to four equivalent Pr3+ atoms.