Crystal structure of thorium nitrate pentahydrate by X‐ray diffraction

Crystals of Th(NO3)4 • 5H20 are orthorhombic, space group Fdd2, a= 11.182, b= 22.873, c= 10-573 A, Z = 8. Thorium has three water molecules and eight oxygen atoms from four nitrate ions as neighbors in a highly polar arrangement. All hydrogen atoms are in hydrogen bonds 2.71 to 2.96 A in length. Average bond distances are: Th-O (water) 2-46 A, Th-O (nitrate) 2.57 A, N-O (next to Th) 1.27 A, N-O (terminal) 1-22 A. An error of about 0.05 A is made in the position of the thorium atom if anomalous dispersion (Aft'= 9) is neglected.