Tris(nitrato-² O,O′)bis-(1,10-phenanthroline-² N,N′)holmium(III)

In the title compound, [Ho(NO3)3(C12H8N2)2], the ten-coordinate Ho ^III ion is chelated by four N atoms from two phenanthroline (phen) ligands and six O atoms from three bidentate nitrate groups. The environment around the Ho atom can be described as a distorted bicapped square anti-prism. Two phenanthroline ligands form a dihedral angle of 43.72 (13)°. Short inter-molecular distances between the centroids of the six-membered rings [3.6887 (14)-3.8374 (16) Å] indicate the existence of π-π inter-actions, which link the mol-ecules into stacks extended in the [10 ] direction. The crystal packing is further stabilized by weak inter-molecular C - H⋯O hydrogen bonds.