Structure, electrical transport, and magnetic properties of the misfit layer compound (CeS)1.16NbS2, “CeNbS3”

(CeS)1.16NbS2 is a misfit layer compound built of alternate double layers of CeS, approximately a {100} slice of NaCl type CeS, and sandwiches of NbS2 with Nb in slightly distorted trigonal prisms of sulfur. The two structural units in the composite crystal are described in centered orthorhombic lattices: a1 = 5.727(1), Å, b1 = 5.765(1), Å, c1 = 11.41(1), Å, space group Cm2a, Z = 4 for the CeS lattice and a2 = 3.311(1), Å, b2 = 5.765(1), Å, c2 = 22.82(2), Å, space group Fm2m, Z = 4 for the NbS2 lattice. Corresponding axes are parallel and the stacking direction is c. Refinements of the CeS part, the NbS2 part, and the common projection using 889, 288, and 135 reflections, respectively, converged to RF = 0.048, 0.069, and 0.072, respectively. The electrical conduction is metallic with a strong anisotropy, the resistivity along the c axis, ϱc, being about 104 larger than the in-plane resistivity ϱab. The conduction is by holes in an almost filled 4dz2 band of the NbS2 part of the structure, indicating electron transfer from the CeS part to the NbS2 part of the structure. The magnetic properties show down to 80 K a Curie Weiss behavior with a Curie constant close to that of CeS with the scheme, Ce3+(e−)S2−; χ−1 goes to zero with decreasing temperature after a small discontinuous drop at about 50 K