X-ray powder diffraction and 57Fe Mossbauer spectroscopy study on Fe0.47NbS2

The crystal structure of Fe0.47NbS2 was refined using X-ray powder diffraction. Fe0.47NbS2 crystallises in the space group P6(3)22 with the unit cell parameters a=5.7905(2) Angstrom and c=12.3891(2) Angstrom. The NbS2 sublattice of Fe0.47NbS2 is similar to 2H-NbS2. The niobium atoms are coordinated trigonal prismatically by sulfur atoms. Sandwiches of NbS2 are stacked onto each other along the c direction, separated by van-der-Waals gaps. The iron atoms are located inside the van-der-Waals gaps on three symmetrically nonequivalent positions. The distribution over these three positions is not uniform. The valence state of the iron atoms was investigated by Mossbauer spectroscopy. The Mossbauer spectroscopy shows that the iron is predominantly ferric and high spin, but a minor part is low spin. (C) 2002 Elsevier Science B.V. All rights reserved.