Crystal structure of hexakis(1,8-naphthyridine)praseodymium(III) perchlorate Academic Article uri icon

abstract

  • Crystals of hexakis(1,8-naphthyridine)praseodymium(III) perchlorate, (C8H6N2)6Pr(ClO4)3, are monoclinic, with space group P21/c. The cell dimensions are a = 13.748 (3) Å, b = 16.979 (6) Å, c = 22.949 (8) Å, and β = 107.34 (1)°, V = 5113.14 Å3. With Z = 4 the density is calculated to be 1.5850 g cm−3 which compares to a density measured by flotation in a KI solution of 1.583 g cm−3. A total of 2263 intensities above background were collected with a scintillation counter automated diffractometer by the θ-2θ scan method. The structure was refined by block-diagonal least-squares methods to a conventional RF factor of 0.049 and a weighted residual RwF of 0.063. Anisotropic thermal parameters were obtained only for the metal atom and perchlorate groups. All six naphthyridine rings act as bidentate ligands forming a distorted icosahedron of nitrogen atoms about the metal. Pr-N bond distances range from 2.735 (12) to 2.768 (11) Å. Distortion of the icosahedron results principally from the unequal lengths of the nitrogen-nitrogen interatomic distances. Those which occur within individual naphthyridine ring systems are short averaging 2.257 (12) Å while those between adjacent nitrogen atoms in two different naphthyridine rings range from 2.890 (16) to 3.195 (16) Å. The rings are also arranged such that a patohedron is not formed. © 1977, American Chemical Society. All rights reserved.

author list (cited authors)

  • Clearfield, A., Gopal, R., & Olsen, R. W.

citation count

  • 38

publication date

  • April 1977