Lanthanoiddisulfide – Synthesen und Kristallstrukturen von α -CeS
2, α -NdS
2, β -LaS
2, β -CeS
2und β -PrS
2Rare Earth Metal Disulfides – Syntheses and Crystal Structures ofα-CeS2,α-NdS2,β-LaS2, β-CeS2, andβ-PrS2
Thomas Schleida, Petra Lauxmanna, Christian Grafb, Christian Bartschb und Thomas Doertb
aInstitut f¨ur Anorganische Chemie, Universit¨at Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
bAnorganische Chemie II, Technische Universit¨at Dresden, Helmholtzstraße 6, 01062 Dresden, Germany
Reprint requests to PD Dr. Thomas Doert. Fax: +49 351 463-37287.
E-mail: thomas.doert@chemie.tu-dresden.de
Z. Naturforsch.2009,64b,189 – 196; received October 23, 2008
In memoriam Dr. Karlheinz Schmidt
α-CeS2andα-NdS2were obtained by a metathesis reaction of the anhydrous trichloridesLnCl3 (Ln= Ce, Nd) and Na2S2 at 1070 K. The two compounds adopt a monoclinic structure type, the so-called CeSe2orα-type of the rare earth metal dichalcogenides (space groupP21/a), with lattice parameters ofa= 8.105(3),b= 4.075(1),c= 8.097(3) ˚A,β = 90.03(4)◦for CeS2anda= 8.008(2), b= 4.019(1),c= 8.032(2) ˚A,β= 90.00(3)◦for NdS2. Single crystals ofβ-LaS2,β-CeS2andβ-PrS2
were obtained as by-products in the syntheses of the ternary copper sulfides CuLnS2by reacting the elemental educts (Cu, S andLn= La, Ce, Pr) in a CsCl fluxat 970 K. These compounds adopt the orthorhombicβ-LaS2structure type (space groupPnma) with lattice parameters ofa= 8.140(1),b= 16.379(1),c= 4.144(1) ˚A forβ-LaS2,a= 8.068(1),b= 16.216(1),c= 4.095(1) ˚A forβ-CeS2, and a= 8.044(1),b= 16.160(1),c= 4.073(1) ˚A forβ-PrS2.
Key words:Rare Earth Elements, Sulfur, Disulfides, ZrSSi-type Super-structure
