Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Synthesis, crystal and electronic structure of the new sodium chain sulfido cobaltates(II), Na 3 CoS 3 and Na 5 (CoS 2 ) 2 (Br)

Synthesis, crystal and electronic structure of the new sodium chain sulfido cobaltates(II), Na 3... Abstract The sulfido cobaltate(II) Na 3 CoS 3 was synthesized from stoichiometric quantities of Na 2 S, elemental cobalt and sulfur at a maximum temperature of 1100°C. According to Na 3 CoS 3 =Na 12 (Co 2 S 5 (S 2 ))(Co 2 S 3 (S 2 )) the orthorhombic structure of a new type (space group Cmc 2 1 , a =884.24(2), b =2177.38(5), c =1193.20(3) pm, Z =12, R 1=0.0205) contains two different anions: i. dimers (Co 2 S 5 (S 2 )) 8− of two edge-sharing (CoS 4 ) tetrahedra with five sulfido and one η 1 -disulfido ligand; ii. chains ∞ 1 ( Co 2 S 3 ( S 2 ) ) 4 − $_\infty ^1{({\rm{C}}{{\rm{o}}_2}{{\rm{S}}_3}({{\rm{S}}_2}))^{4 - }}$ of (CoS 4 ) tetrahedra connected via μ -sulfido (3×) besides μ -1,2-disulfido (1×) ligands. The second title compound, Na 5 (CoS 2 ) 2 (Br), which has been likewise synthesized as a pure phase from stoichiometric quantities of Na 2 S, Co, S and NaBr, is isotypic to Na 5 (CoS 2 ) 2 (S) (Na 6 PbO 5 type; tetragonal, space group I 4 mm , a =914.58(7), c =625.59(5) pm; R 1=0.0412). The structure contains linear chains ∞ 1 ( CoS 4 / 2 ) 2 − $_\infty ^1{({\rm{Co}}{{\rm{S}}_{4/2}})^{2 - }}$ running along the tetragonal c axis. In between, Br − ions are interspersed, which are coordinated by square pyramids of Na + ions. The isotypic hydrogensulfide Na 5 (CoS 2 ) 2 (SH) was obtained via the addition of NaSH. Several synthetic and structural arguments suggest that Na 5 (CoS 2 ) 2 (SH) and the previously described pure sulfide are the same compound. The results of DFT band structure calculations (GGA+ U , AFM spin ordering) are used to discuss and compare the chemical bonding in the new sulfido cobaltates(II) with that of the reference compound Na 2 (CoS 2 ). They also allow for obtaining insight into the superexchange path, which is responsible for the strong antiferromagnetic Co spin ordering along the chains. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Zeitschrift für Naturforschung B de Gruyter

Synthesis, crystal and electronic structure of the new sodium chain sulfido cobaltates(II), Na 3 CoS 3 and Na 5 (CoS 2 ) 2 (Br)

Download PDF
13 pages

Loading next page...
 
/lp/de-gruyter/synthesis-crystal-and-electronic-structure-of-the-new-sodium-chain-jH66iL3Q17

References (39)

Publisher
de Gruyter
Copyright
Copyright © 2016 by the
ISSN
0932-0776
eISSN
1865-7117
DOI
10.1515/znb-2016-0179
Publisher site
See Article on Publisher Site

Abstract

Abstract The sulfido cobaltate(II) Na 3 CoS 3 was synthesized from stoichiometric quantities of Na 2 S, elemental cobalt and sulfur at a maximum temperature of 1100°C. According to Na 3 CoS 3 =Na 12 (Co 2 S 5 (S 2 ))(Co 2 S 3 (S 2 )) the orthorhombic structure of a new type (space group Cmc 2 1 , a =884.24(2), b =2177.38(5), c =1193.20(3) pm, Z =12, R 1=0.0205) contains two different anions: i. dimers (Co 2 S 5 (S 2 )) 8− of two edge-sharing (CoS 4 ) tetrahedra with five sulfido and one η 1 -disulfido ligand; ii. chains ∞ 1 ( Co 2 S 3 ( S 2 ) ) 4 − $_\infty ^1{({\rm{C}}{{\rm{o}}_2}{{\rm{S}}_3}({{\rm{S}}_2}))^{4 - }}$ of (CoS 4 ) tetrahedra connected via μ -sulfido (3×) besides μ -1,2-disulfido (1×) ligands. The second title compound, Na 5 (CoS 2 ) 2 (Br), which has been likewise synthesized as a pure phase from stoichiometric quantities of Na 2 S, Co, S and NaBr, is isotypic to Na 5 (CoS 2 ) 2 (S) (Na 6 PbO 5 type; tetragonal, space group I 4 mm , a =914.58(7), c =625.59(5) pm; R 1=0.0412). The structure contains linear chains ∞ 1 ( CoS 4 / 2 ) 2 − $_\infty ^1{({\rm{Co}}{{\rm{S}}_{4/2}})^{2 - }}$ running along the tetragonal c axis. In between, Br − ions are interspersed, which are coordinated by square pyramids of Na + ions. The isotypic hydrogensulfide Na 5 (CoS 2 ) 2 (SH) was obtained via the addition of NaSH. Several synthetic and structural arguments suggest that Na 5 (CoS 2 ) 2 (SH) and the previously described pure sulfide are the same compound. The results of DFT band structure calculations (GGA+ U , AFM spin ordering) are used to discuss and compare the chemical bonding in the new sulfido cobaltates(II) with that of the reference compound Na 2 (CoS 2 ). They also allow for obtaining insight into the superexchange path, which is responsible for the strong antiferromagnetic Co spin ordering along the chains.

Journal

Zeitschrift für Naturforschung B – de Gruyter

Published: Dec 1, 2016

There are no references for this article.