Synthesis and study of Sr-substituted misfit layer sulfides
2005 (English)In: Materials Research Bulletin, ISSN 0025-5408, Vol. 40, no 1, 79-91 p.Article in journal (Refereed) Published
Two series of [(Ln1/3Sr2/3S)1.5]1.15NbS2 (1.5Q/1H) and (Ln1−xSrxS)1+yNbS2 (1Q/1H) misfit layer sulfides have been synthesised and studied by X-ray powder and single crystal diffraction, EDX-analysis and magnetic measurements. For the early lanthanides (Ln = La, Ce) only the (Ln1−xSrxS)1+yNbS2 (x < 0.40–0.45, y = 0.15–0.17) compounds were formed whereas for late lanthanides (Ln = Pr, Nd, Sm, Gd–Er, Yb, Lu), and yttrium, both types of phases can be obtained. The crystal structure of (Pr0.55Sr0.45S)1.15NbS2 has been refined on the basis of X-ray single crystal data using the superspace approach. It consists of double layers [Pr0.55Sr0.45S] of NaCl-type (Q-part: a = 5.799(3) Å, b = 5.810(2) Å, c = 23.331(9) Å, z = 4) and NbS2-sandwiches (H-part: a = 3.332(3) Å), z = 8, yielding a q-vector q = (α 0 0), α = 0.74) alternating along the c-direction. The superspace group pair is Fm2m (α 0 0):Fm2m (α 0 0) (No. 42.7). The refinement converged to Rw(obs) = 0.069. According to the structure refinement and EDX-analysis data in the [Pr0.55Sr0.45S]-slab almost half of the Pr-atoms are randomly replaced by Sr. The minimal formal value of charge transfer from the Q- to the H-part of the structure necessary to stabilise the misfit Nb-based layer sulfides has been estimated as about 0.6 ē per Nb atom.
Place, publisher, year, edition, pages
Elsevier , 2005. Vol. 40, no 1, 79-91 p.
Research subject Chemical Physics
IdentifiersURN: urn:nbn:se:su:diva-23188DOI: 10.1016/j.materresbull.2004.09.017OAI: oai:DiVA.org:su-23188DiVA: diva2:190550
Part of urn:nbn:se:su:diva-1772004-05-192004-05-192009-12-30Bibliographically approved