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Volume 68 
Part 1 
Page i2  
January 2012  

Received 14 November 2011
Accepted 1 December 2011
Online 7 December 2011

Key indicators
Single-crystal X-ray study
T = 293 K
Mean [sigma](Sm-Se) = 0.001 Å
Disorder in main residue
R = 0.035
wR = 0.072
Data-to-parameter ratio = 29.7
Details
Open access

Cs3Sm7Se12

aInstitut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
Correspondence e-mail: schleid@iac.uni-stuttgart.de

The title compound, tricaesium heptasamarium(III) dodecaselenide, is setting a new starting point for realization of the channel structure of the Cs3M7Se12 series, now with M = Sm, Gd-Er. This Cs3Y7Se12-type arrangement is structurally based on the Z-type sesquiselenides M2Se3 adopting the Sc2S3 structure. Thus, the structural set-up of Cs3Sm7Se12 consists of edge- and vertex-connected [SmSe6]9- octahedra [dØ(Sm3+ - Se2-) = 2.931 Å], forming a rock-salt-related network [Sm7Se12]3- with channels along [001] that are apt to take up monovalent cations (here Cs+) with coordination numbers of 7 + 1 for one and of 6 for the second cation. The latter cation has a trigonal-prismatic coordination and shows half-occupancy, resulting in an impossible short distance [2.394 (4) Å] between symmetrically coupled Cs+ cations of the same kind. While one Sm atom occupies Wyckoff position 2b with site symmetry ..2/m, all other 11 crystallographically different atoms (namely 2 × Cs, 3 × Sm and 6 × Se) are located at Wyckoff positions 4g with site symmetry ..m.

Related literature

For prototypic Cs3Y7Se12 or Rb3Yb7Se12, see: Folchnandt & Schleid (1996[Folchnandt, M. & Schleid, Th. (1996). Z. Kristallogr. Suppl. 12, 125.]); Kim et al. (1996[Kim, S.-J., Park, S.-J., Yun, H. & Do, J. (1996). Inorg. Chem. 35, 5283-5289.]). For other representatives of the A3M7Ch12 series, see: Folchnandt & Schleid (1997[Folchnandt, M. & Schleid, Th. (1997). Z. Anorg. Allg. Chem. 623, 1501-1502.], 1998[Folchnandt, M. & Schleid, Th. (1998). Z. Anorg. Allg. Chem. 624, 1595-1600.], 2000[Folchnandt, M. & Schleid, Th. (2000). Z. Kristallogr. New Cryst. Struct. 215, 9-10.]); Tougaît et al. (2001[Tougaît, O., Noël, H. & Ibers, J. A. (2001). Solid State Sci. 3, 513-518.]); Lissner et al. (2002[Lissner, F., Hartenbach, I. & Schleid, Th. (2002). Z. Anorg. Allg. Chem. 628, 1552-1555.]). A detailed description of the relation between the crystal structures of the Cs3M7Se12 series and Z-type Sc2Ch3 (Dismukes & White, 1964[Dismukes, J. P. & White, J. G. (1964). Inorg. Chem. 3, 1220-1228.]) is provided by Folchnandt & Schleid (1998[Folchnandt, M. & Schleid, Th. (1998). Z. Anorg. Allg. Chem. 624, 1595-1600.]).

Experimental

Crystal data
  • Cs3Sm7Se12

  • Mr = 2398.70

  • Orthorhombic, P n n m

  • a = 13.0387 (9) Å

  • b = 26.6742 (19) Å

  • c = 4.2351 (3) Å

  • V = 1472.95 (18) Å3

  • Z = 2

  • Mo K[alpha] radiation

  • [mu] = 32.19 mm-1

  • T = 293 K

  • 0.10 × 0.07 × 0.05 mm

Data collection
  • Stoe IPDS-I diffractometer

  • Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1999[Stoe & Cie (1999). X-SHAPE. Stoe & Cie, Darmstadt, Germany.]) Tmin = 0.115, Tmax = 0.216

  • 15080 measured reflections

  • 2135 independent reflections

  • 1587 reflections with I > 2[sigma](I)

  • Rint = 0.065

Refinement
  • R[F2 > 2[sigma](F2)] = 0.035

  • wR(F2) = 0.072

  • S = 0.97

  • 2135 reflections

  • 72 parameters

  • [Delta][rho]max = 2.09 e Å-3

  • [Delta][rho]min = -1.78 e Å-3

Table 1
Selected bond lengths (Å)

Cs1-Se4i 3.6071 (12)
Cs1-Se4ii 3.6071 (12)
Cs1-Se6ii 3.7129 (12)
Cs1-Se6i 3.7129 (12)
Cs1-Se3iii 3.7639 (14)
Cs1-Se5i 3.8053 (12)
Cs1-Se5ii 3.8053 (12)
Cs1-Se1 4.5421 (14)
Cs2-Se2ii 3.5286 (16)
Cs2-Se2i 3.5286 (16)
Cs2-Se2v 3.6917 (17)
Cs2-Se2vi 3.6917 (17)
Cs2-Se5iii 3.719 (2)
Cs2-Se6iii 3.924 (2)
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) -x+1, -y+1, -z; (iv) -x+1, -y, -z; (v) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z-{\script{1\over 2}}]; (vi) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: DIF4 (Stoe & Cie, 1992[Stoe & Cie (1992). DIF4 and REDU4. Stoe & Cie, Darmstadt, Germany.]); cell refinement: DIF4; data reduction: REDU4 (Stoe & Cie, 1992[Stoe & Cie (1992). DIF4 and REDU4. Stoe & Cie, Darmstadt, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.


Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WM2561 ).


Acknowledgements

This work was supported by the State of Baden-Württemberg (Stuttgart) and the German Research Foundation (DFG; Bonn) within the funding programme Open Access Publishing. We thank Dr Falk Lissner for the data collection.

References

Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.
Dismukes, J. P. & White, J. G. (1964). Inorg. Chem. 3, 1220-1228.  [CrossRef] [ChemPort] [ISI]
Folchnandt, M. & Schleid, Th. (1996). Z. Kristallogr. Suppl. 12, 125.
Folchnandt, M. & Schleid, Th. (1997). Z. Anorg. Allg. Chem. 623, 1501-1502.  [CrossRef] [ChemPort]
Folchnandt, M. & Schleid, Th. (1998). Z. Anorg. Allg. Chem. 624, 1595-1600.  [CrossRef] [ChemPort]
Folchnandt, M. & Schleid, Th. (2000). Z. Kristallogr. New Cryst. Struct. 215, 9-10.  [ChemPort]
Kim, S.-J., Park, S.-J., Yun, H. & Do, J. (1996). Inorg. Chem. 35, 5283-5289.  [CrossRef] [ChemPort] [ISI]
Lissner, F., Hartenbach, I. & Schleid, Th. (2002). Z. Anorg. Allg. Chem. 628, 1552-1555.  [CrossRef] [ChemPort]
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.  [CrossRef] [details]
Stoe & Cie (1992). DIF4 and REDU4. Stoe & Cie, Darmstadt, Germany.
Stoe & Cie (1999). X-SHAPE. Stoe & Cie, Darmstadt, Germany.
Tougaît, O., Noël, H. & Ibers, J. A. (2001). Solid State Sci. 3, 513-518.


Acta Cryst (2012). E68, i2  [ doi:10.1107/S1600536811051919 ]

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