Crystal architecture of R₂SnS₅ (R = Pr, Nd, Gd and Tb): crystal structure relationships in chalcogenides

The crystal structure of the R₂SnS₅ (R = Pr, Nd, Gd and Tb) compounds has been investigated using X-ray single-crystal diffraction. Crystal architecture and structural relationships among U₃S₅, Y₂HfS₅, R₂SnS₅ compounds are discussed and a structural origin is determined. It is shown that the complex architecture of the crystal structure of Eu₅Sn₃S₁₂ is a result of interweaving of the simple crystal structures. The location of the copper ions in the non-stoichiometric compound Y₂Cu_0.20Sn_0.95S₅ is proposed on the basis of comparative analysis of the R-S interatomic distances in the R₂SnS₅ series of compounds.

Computing details

For all compounds, data collection: CrysAlis 1.171.32.6; cell refinement: CrysAlis 1.171.32.6; data reduction: CrysAlis 1.171.32.6; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997).

Figures

(pr)

Crystal data

Pr2S5Sn	F(000) = 496
Mr = 560.81	Dx = 5.382 Mg m^−3
Orthorhombic, Pbam	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2 2ab	Cell parameters from 424 reflections
a = 7.8195 (9) Å	θ = 3.2–27.5°
b = 11.2145 (14) Å	µ = 18.82 mm^−1
c = 3.9462 (5) Å	T = 293 K
V = 346.05 (7) Å^3	Prism, dark red
Z = 2	0.09 × 0.08 × 0.06 mm

Data collection

KUMA KM-4 with area CCD detector diffractometer	452 independent reflections
Radiation source: fine-focus sealed tube	424 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.041
Detector resolution: 1024x1024 with blocks 2x2, 33.133pixel/mm pixels mm^-1	θmax = 27.5°, θmin = 3.2°
ω–scan	h = −10→9
Absorption correction: numerical M. Mayer, CrysAlis Data Reduction Program, Oxford Diffraction Ltd, 2007	k = −12→14
Tmin = 0.239, Tmax = 0.458	l = −5→4
4036 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.013	w = 1/[σ^2(Fo^2) + (0.0102P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.025	(Δ/σ)max = 0.001
S = 1.12	Δρmax = 0.64 e Å^−3
452 reflections	Δρmin = −0.70 e Å^−3
28 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0093 (4)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
ND1	0.43360 (3)	0.169372 (18)	0.5000	0.00845 (9)
Sn1	0.0000	0.0000	0.0000	0.00849 (11)
S1	0.81432 (12)	0.07439 (8)	0.5000	0.0097 (2)
S2	0.15009 (12)	0.20120 (8)	0.0000	0.0083 (2)
S3	0.5000	0.0000	0.0000	0.0094 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
ND1	0.01044 (13)	0.00759 (13)	0.00732 (14)	0.00072 (7)	0.000	0.000
Sn1	0.0101 (2)	0.00657 (18)	0.0088 (2)	−0.00151 (13)	0.000	0.000
S1	0.0084 (5)	0.0123 (5)	0.0084 (5)	0.0017 (3)	0.000	0.000
S2	0.0088 (5)	0.0072 (4)	0.0090 (5)	−0.0003 (3)	0.000	0.000
S3	0.0114 (7)	0.0084 (6)	0.0085 (8)	0.0011 (5)	0.000	0.000

Geometric parameters (Å, º)

ND1—S3	2.7876 (3)	Sn1—S1^viii	2.5879 (6)
ND1—S3^i	2.7876 (3)	Sn1—S1^v	2.5879 (6)
ND1—S2^ii	2.9775 (7)	Sn1—S1^ix	2.5879 (6)
ND1—S2^iii	2.9775 (7)	Sn1—S1^x	2.5879 (6)
ND1—S2	2.9892 (8)	S1—Sn1^xi	2.5879 (6)
ND1—S2^i	2.9892 (8)	S1—Sn1^xii	2.5879 (6)
ND1—S1^iv	3.0211 (10)	S1—ND1^iii	3.0211 (10)
ND1—S1	3.1618 (10)	S2—ND1^xiii	2.9775 (7)
ND1—ND1^v	3.9382 (6)	S2—ND1^iv	2.9775 (7)
ND1—ND1^i	3.9462 (5)	S2—ND1^vi	2.9892 (8)
ND1—ND1^vi	3.9462 (5)	S3—ND1^x	2.7876 (3)
Sn1—S2^vii	2.5433 (9)	S3—ND1^vi	2.7876 (3)
Sn1—S2	2.5433 (9)	S3—ND1^v	2.7876 (3)
S3—ND1—S3^i	90.116 (12)	S3^i—ND1—ND1^vi	135.058 (6)
S3—ND1—S2^ii	134.053 (19)	S2^ii—ND1—ND1^vi	131.504 (13)
S3^i—ND1—S2^ii	75.949 (17)	S2^iii—ND1—ND1^vi	48.496 (13)
S3—ND1—S2^iii	75.949 (17)	S2—ND1—ND1^vi	48.694 (13)
S3^i—ND1—S2^iii	134.053 (19)	S2^i—ND1—ND1^vi	131.306 (13)
S2^ii—ND1—S2^iii	83.01 (3)	S1^iv—ND1—ND1^vi	90.0
S3—ND1—S2	75.658 (16)	S1—ND1—ND1^vi	90.0
S3^i—ND1—S2	133.371 (18)	ND1^v—ND1—ND1^vi	90.0
S2^ii—ND1—S2	143.212 (13)	ND1^i—ND1—ND1^vi	180.000 (17)
S2^iii—ND1—S2	85.758 (11)	S2^vii—Sn1—S2	180.000 (19)
S3—ND1—S2^i	133.371 (18)	S2^vii—Sn1—S1^viii	91.55 (3)
S3^i—ND1—S2^i	75.658 (16)	S2—Sn1—S1^viii	88.45 (3)
S2^ii—ND1—S2^i	85.758 (11)	S2^vii—Sn1—S1^v	88.45 (3)
S2^iii—ND1—S2^i	143.212 (13)	S2—Sn1—S1^v	91.55 (3)
S2—ND1—S2^i	82.61 (3)	S1^viii—Sn1—S1^v	180.00 (4)
S3—ND1—S1^iv	134.879 (6)	S2^vii—Sn1—S1^ix	91.55 (3)
S3^i—ND1—S1^iv	134.879 (6)	S2—Sn1—S1^ix	88.45 (3)
S2^ii—ND1—S1^iv	73.25 (2)	S1^viii—Sn1—S1^ix	99.36 (3)
S2^iii—ND1—S1^iv	73.25 (2)	S1^v—Sn1—S1^ix	80.64 (3)
S2—ND1—S1^iv	69.97 (2)	S2^vii—Sn1—S1^x	88.45 (3)
S2^i—ND1—S1^iv	69.97 (2)	S2—Sn1—S1^x	91.55 (3)
S3—ND1—S1	66.115 (12)	S1^viii—Sn1—S1^x	80.64 (3)
S3^i—ND1—S1	66.115 (12)	S1^v—Sn1—S1^x	99.36 (3)
S2^ii—ND1—S1	68.22 (2)	S1^ix—Sn1—S1^x	180.00 (3)
S2^iii—ND1—S1	68.22 (2)	Sn1^xi—S1—Sn1^xii	99.36 (3)
S2—ND1—S1	137.606 (14)	Sn1^xi—S1—ND1^iii	97.67 (2)
S2^i—ND1—S1	137.606 (14)	Sn1^xii—S1—ND1^iii	97.67 (2)
S1^iv—ND1—S1	127.67 (3)	Sn1^xi—S1—ND1	129.558 (17)
S3—ND1—ND1^v	45.058 (6)	Sn1^xii—S1—ND1	129.558 (17)
S3^i—ND1—ND1^v	45.058 (6)	ND1^iii—S1—ND1	88.30 (2)
S2^ii—ND1—ND1^v	108.682 (19)	Sn1—S2—ND1^xiii	99.79 (3)
S2^iii—ND1—ND1^v	108.682 (19)	Sn1—S2—ND1^iv	99.79 (3)
S2—ND1—ND1^v	108.103 (18)	ND1^xiii—S2—ND1^iv	83.01 (3)
S2^i—ND1—ND1^v	108.103 (18)	Sn1—S2—ND1	103.67 (3)
S1^iv—ND1—ND1^v	177.30 (2)	ND1^xiii—S2—ND1	156.53 (3)
S1—ND1—ND1^v	55.026 (17)	ND1^iv—S2—ND1	92.433 (11)
S3—ND1—ND1^i	135.058 (6)	Sn1—S2—ND1^vi	103.67 (3)
S3^i—ND1—ND1^i	44.942 (6)	ND1^xiii—S2—ND1^vi	92.433 (12)
S2^ii—ND1—ND1^i	48.496 (13)	ND1^iv—S2—ND1^vi	156.53 (3)
S2^iii—ND1—ND1^i	131.504 (13)	ND1—S2—ND1^vi	82.61 (3)
S2—ND1—ND1^i	131.306 (13)	ND1—S3—ND1^x	180.000 (8)
S2^i—ND1—ND1^i	48.694 (13)	ND1—S3—ND1^vi	90.116 (12)
S1^iv—ND1—ND1^i	90.0	ND1^x—S3—ND1^vi	89.884 (12)
S1—ND1—ND1^i	90.0	ND1—S3—ND1^v	89.884 (12)
ND1^v—ND1—ND1^i	90.0	ND1^x—S3—ND1^v	90.116 (12)
S3—ND1—ND1^vi	44.942 (6)	ND1^vi—S3—ND1^v	180.000 (6)

Symmetry codes: (i) x, y, z+1; (ii) x+1/2, −y+1/2, z+1; (iii) x+1/2, −y+1/2, z; (iv) x−1/2, −y+1/2, z; (v) −x+1, −y, −z+1; (vi) x, y, z−1; (vii) −x, −y, −z; (viii) x−1, y, z−1; (ix) x−1, y, z; (x) −x+1, −y, −z; (xi) x+1, y, z+1; (xii) x+1, y, z; (xiii) x−1/2, −y+1/2, z−1.

(nd)

Crystal data

Nd2S5Sn	F(000) = 500
Mr = 567.47	Dx = 5.504 Mg m^−3
Orthorhombic, Pbam	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2 2ab	Cell parameters from 392 reflections
a = 7.7721 (14) Å	θ = 3.2–26.7°
b = 11.218 (2) Å	µ = 19.96 mm^−1
c = 3.9272 (9) Å	T = 293 K
V = 342.41 (12) Å^3	Prism, black
Z = 2	0.22 × 0.21 × 0.19 mm

Data collection

KUMA KM-4 with area CCD detector diffractometer	402 independent reflections
Radiation source: fine-focus sealed tube	392 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.094
Detector resolution: 1024x1024 with blocks 2x2, 33.133pixel/mm pixels mm^-1	θmax = 26.7°, θmin = 3.2°
ω–scan	h = −8→9
Absorption correction: numerical M. Mayer, CrysAlis Data Reduction Program, Oxford Diffraction Ltd, 2007	k = −14→14
Tmin = 0.123, Tmax = 0.258	l = −4→4
3642 measured reflections

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F^2 > 2σ(F^2)] = 0.026	Secondary atom site location: difference Fourier map
wR(F^2) = 0.067	w = 1/[σ^2(Fo^2) + (0.030P)^2 + 3.9487P] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max < 0.001
402 reflections	Δρmax = 1.33 e Å^−3
27 parameters	Δρmin = −1.83 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Nd1	0.43909 (6)	0.16988 (4)	0.5000	0.0100 (2)
Sn1	0.0000	0.0000	0.0000	0.0101 (3)
S1	0.8162 (3)	0.0772 (2)	0.5000	0.0117 (5)
S2	0.1544 (3)	0.20048 (19)	0.0000	0.0103 (5)
S3	0.5000	0.0000	0.0000	0.0107 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Nd1	0.0097 (3)	0.0105 (3)	0.0100 (3)	0.00091 (16)	0.000	0.000
Sn1	0.0107 (5)	0.0087 (5)	0.0110 (5)	−0.0023 (3)	0.000	0.000
S1	0.0078 (10)	0.0141 (11)	0.0132 (11)	0.0029 (8)	0.000	0.000
S2	0.0076 (9)	0.0092 (10)	0.0142 (12)	0.0012 (8)	0.000	0.000
S3	0.0112 (15)	0.0087 (14)	0.0123 (15)	0.0005 (11)	0.000	0.000

Geometric parameters (Å, º)

Nd1—S3	2.7770 (5)	Sn1—S1^viii	2.5782 (14)
Nd1—S3^i	2.7770 (5)	Sn1—S1^vi	2.5782 (14)
Nd1—S2^ii	2.9618 (16)	Sn1—S1^ix	2.5782 (14)
Nd1—S2^iii	2.9618 (16)	Sn1—S1^x	2.5782 (14)
Nd1—S2	2.9779 (17)	S1—Sn1^xi	2.5782 (14)
Nd1—S2^i	2.9779 (17)	S1—Sn1^xii	2.5782 (14)
Nd1—S1^iv	2.993 (2)	S1—Nd1^iii	2.993 (2)
Nd1—S1	3.110 (2)	S2—Nd1^xiii	2.9618 (16)
Nd1—Nd1^i	3.9272 (9)	S2—Nd1^iv	2.9618 (16)
Nd1—Nd1^v	3.9272 (9)	S2—Nd1^v	2.9779 (17)
Nd1—Nd1^vi	3.9274 (11)	S3—Nd1^x	2.7770 (5)
Sn1—S2	2.549 (2)	S3—Nd1^vi	2.7770 (5)
Sn1—S2^vii	2.549 (2)	S3—Nd1^v	2.7770 (5)
S3—Nd1—S3^i	90.00 (2)	S3^i—Nd1—Nd1^vi	44.999 (11)
S3—Nd1—S2^ii	135.19 (4)	S2^ii—Nd1—Nd1^vi	109.90 (4)
S3^i—Nd1—S2^ii	76.81 (4)	S2^iii—Nd1—Nd1^vi	109.90 (4)
S3—Nd1—S2^iii	76.81 (4)	S2—Nd1—Nd1^vi	106.92 (4)
S3^i—Nd1—S2^iii	135.19 (4)	S2^i—Nd1—Nd1^vi	106.92 (4)
S2^ii—Nd1—S2^iii	83.06 (6)	S1^iv—Nd1—Nd1^vi	175.35 (5)
S3—Nd1—S2	74.90 (4)	S1—Nd1—Nd1^vi	56.52 (4)
S3^i—Nd1—S2	132.22 (4)	Nd1^i—Nd1—Nd1^vi	90.0
S2^ii—Nd1—S2	143.17 (3)	Nd1^v—Nd1—Nd1^vi	90.0
S2^iii—Nd1—S2	85.76 (2)	S2—Sn1—S2^vii	180.00 (5)
S3—Nd1—S2^i	132.22 (4)	S2—Sn1—S1^viii	87.96 (6)
S3^i—Nd1—S2^i	74.90 (4)	S2^vii—Sn1—S1^viii	92.04 (6)
S2^ii—Nd1—S2^i	85.76 (2)	S2—Sn1—S1^vi	92.04 (6)
S2^iii—Nd1—S2^i	143.17 (3)	S2^vii—Sn1—S1^vi	87.96 (6)
S2—Nd1—S2^i	82.51 (6)	S1^viii—Sn1—S1^vi	180.0
S3—Nd1—S1^iv	134.813 (11)	S2—Sn1—S1^ix	87.96 (6)
S3^i—Nd1—S1^iv	134.813 (11)	S2^vii—Sn1—S1^ix	92.04 (6)
S2^ii—Nd1—S1^iv	73.44 (5)	S1^viii—Sn1—S1^ix	99.21 (7)
S2^iii—Nd1—S1^iv	73.44 (5)	S1^vi—Sn1—S1^ix	80.79 (7)
S2—Nd1—S1^iv	69.74 (5)	S2—Sn1—S1^x	92.04 (6)
S2^i—Nd1—S1^iv	69.74 (5)	S2^vii—Sn1—S1^x	87.96 (6)
S3—Nd1—S1	67.04 (3)	S1^viii—Sn1—S1^x	80.79 (7)
S3^i—Nd1—S1	67.04 (3)	S1^vi—Sn1—S1^x	99.21 (7)
S2^ii—Nd1—S1	68.38 (5)	S1^ix—Sn1—S1^x	180.00 (12)
S2^iii—Nd1—S1	68.38 (5)	Sn1^xi—S1—Sn1^xii	99.21 (7)
S2—Nd1—S1	137.62 (3)	Sn1^xi—S1—Nd1^iii	98.15 (6)
S2^i—Nd1—S1	137.62 (3)	Sn1^xii—S1—Nd1^iii	98.15 (6)
S1^iv—Nd1—S1	128.13 (6)	Sn1^xi—S1—Nd1	129.38 (4)
S3—Nd1—Nd1^i	134.999 (10)	Sn1^xii—S1—Nd1	129.38 (4)
S3^i—Nd1—Nd1^i	45.001 (11)	Nd1^iii—S1—Nd1	89.08 (6)
S2^ii—Nd1—Nd1^i	48.47 (3)	Sn1—S2—Nd1^xiii	99.62 (6)
S2^iii—Nd1—Nd1^i	131.53 (3)	Sn1—S2—Nd1^iv	99.62 (6)
S2—Nd1—Nd1^i	131.25 (3)	Nd1^xiii—S2—Nd1^iv	83.06 (6)
S2^i—Nd1—Nd1^i	48.75 (3)	Sn1—S2—Nd1	104.36 (6)
S1^iv—Nd1—Nd1^i	90.0	Nd1^xiii—S2—Nd1	156.01 (8)
S1—Nd1—Nd1^i	90.0	Nd1^iv—S2—Nd1	92.25 (2)
S3—Nd1—Nd1^v	45.001 (11)	Sn1—S2—Nd1^v	104.36 (6)
S3^i—Nd1—Nd1^v	134.999 (11)	Nd1^xiii—S2—Nd1^v	92.25 (2)
S2^ii—Nd1—Nd1^v	131.53 (3)	Nd1^iv—S2—Nd1^v	156.01 (8)
S2^iii—Nd1—Nd1^v	48.47 (3)	Nd1—S2—Nd1^v	82.51 (6)
S2—Nd1—Nd1^v	48.75 (3)	Nd1^x—S3—Nd1	180.00 (2)
S2^i—Nd1—Nd1^v	131.25 (3)	Nd1^x—S3—Nd1^vi	90.00 (2)
S1^iv—Nd1—Nd1^v	90.0	Nd1—S3—Nd1^vi	90.00 (2)
S1—Nd1—Nd1^v	90.0	Nd1^x—S3—Nd1^v	90.00 (2)
Nd1^i—Nd1—Nd1^v	180.00 (4)	Nd1—S3—Nd1^v	90.00 (2)
S3—Nd1—Nd1^vi	44.999 (11)	Nd1^vi—S3—Nd1^v	180.000 (13)

Symmetry codes: (i) x, y, z+1; (ii) x+1/2, −y+1/2, z+1; (iii) x+1/2, −y+1/2, z; (iv) x−1/2, −y+1/2, z; (v) x, y, z−1; (vi) −x+1, −y, −z+1; (vii) −x, −y, −z; (viii) x−1, y, z−1; (ix) x−1, y, z; (x) −x+1, −y, −z; (xi) x+1, y, z+1; (xii) x+1, y, z; (xiii) x−1/2, −y+1/2, z−1.

(gd)

Crystal data

Gd2S5Sn	F(000) = 516
Mr = 593.49	Dx = 5.907 Mg m^−3
Orthorhombic, Pbam	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2 2ab	Cell parameters from 348 reflections
a = 7.7330 (17) Å	θ = 3.2–26.7°
b = 11.290 (2) Å	µ = 24.80 mm^−1
c = 3.8217 (9) Å	T = 293 K
V = 333.66 (13) Å^3	Prism, black
Z = 2	0.10 × 0.03 × 0.02 mm

Data collection

KUMA KM-4 with area CCD detector diffractometer	401 independent reflections
Radiation source: fine-focus sealed tube	348 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.062
Detector resolution: 1024x1024 with blocks 2x2, 33.133pixel/mm pixels mm^-1	θmax = 26.7°, θmin = 3.2°
ω–scan	h = −9→9
Absorption correction: numerical M. Mayer, CrysAlis Data Reduction Program, Oxford Diffraction Ltd, 2007	k = −14→14
Tmin = 0.242, Tmax = 0.546	l = −4→4
3712 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.018	w = 1/[σ^2(Fo^2) + (0.0053P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.027	(Δ/σ)max < 0.001
S = 0.87	Δρmax = 0.77 e Å^−3
401 reflections	Δρmin = −0.96 e Å^−3
28 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0222 (6)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Gd1	0.46231 (5)	0.17255 (4)	0.5000	0.00938 (16)
Sn1	0.0000	0.0000	0.0000	0.0090 (2)
S1	0.8270 (2)	0.09066 (18)	0.5000	0.0097 (5)
S2	0.1701 (2)	0.19536 (18)	0.0000	0.0086 (4)
S3	0.5000	0.0000	0.0000	0.0095 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Gd1	0.0113 (2)	0.0095 (2)	0.0073 (2)	0.00074 (19)	0.000	0.000
Sn1	0.0116 (5)	0.0085 (4)	0.0069 (4)	−0.0001 (3)	0.000	0.000
S1	0.0107 (10)	0.0105 (10)	0.0079 (11)	0.0018 (9)	0.000	0.000
S2	0.0091 (9)	0.0089 (11)	0.0077 (10)	−0.0011 (8)	0.000	0.000
S3	0.0114 (16)	0.0113 (14)	0.0057 (13)	−0.0010 (11)	0.000	0.000

Geometric parameters (Å, º)

Gd1—S3	2.7444 (5)	Sn1—S1^vi	2.5472 (13)
Gd1—S3^i	2.7444 (5)	Sn1—S1^ix	2.5472 (13)
Gd1—S1^ii	2.871 (2)	Sn1—S2^x	2.568 (2)
Gd1—S2^iii	2.9082 (15)	Sn1—S2	2.568 (2)
Gd1—S2^iv	2.9082 (15)	S1—Sn1^xi	2.5472 (13)
Gd1—S1	2.968 (2)	S1—Sn1^xii	2.5472 (13)
Gd1—S2	2.9704 (15)	S1—Gd1^iv	2.871 (2)
Gd1—S2^i	2.9704 (15)	S2—Gd1^ii	2.9082 (15)
Gd1—Gd1^v	3.8217 (9)	S2—Gd1^xiii	2.9082 (15)
Gd1—Gd1^i	3.8217 (9)	S2—Gd1^v	2.9704 (15)
Gd1—Gd1^vi	3.9396 (12)	S3—Gd1^ix	2.7444 (5)
Sn1—S1^vii	2.5472 (13)	S3—Gd1^v	2.7444 (5)
Sn1—S1^viii	2.5472 (13)	S3—Gd1^vi	2.7444 (5)
S3—Gd1—S3^i	88.26 (2)	S3^i—Gd1—Gd1^vi	44.130 (11)
S3—Gd1—S1^ii	134.407 (14)	S1^ii—Gd1—Gd1^vi	167.14 (4)
S3^i—Gd1—S1^ii	134.407 (14)	S2^iii—Gd1—Gd1^vi	115.17 (4)
S3—Gd1—S2^iii	139.71 (4)	S2^iv—Gd1—Gd1^vi	115.17 (4)
S3^i—Gd1—S2^iii	81.25 (3)	S1—Gd1—Gd1^vi	63.34 (4)
S1^ii—Gd1—S2^iii	73.97 (5)	S2—Gd1—Gd1^vi	101.44 (4)
S3—Gd1—S2^iv	81.25 (3)	S2^i—Gd1—Gd1^vi	101.44 (4)
S3^i—Gd1—S2^iv	139.71 (4)	Gd1^v—Gd1—Gd1^vi	90.0
S1^ii—Gd1—S2^iv	73.97 (5)	Gd1^i—Gd1—Gd1^vi	90.0
S2^iii—Gd1—S2^iv	82.15 (5)	S1^vii—Sn1—S1^viii	97.21 (7)
S3—Gd1—S1	71.21 (3)	S1^vii—Sn1—S1^vi	180.0
S3^i—Gd1—S1	71.21 (3)	S1^viii—Sn1—S1^vi	82.79 (7)
S1^ii—Gd1—S1	129.52 (5)	S1^vii—Sn1—S1^ix	82.79 (7)
S2^iii—Gd1—S1	68.57 (5)	S1^viii—Sn1—S1^ix	180.00 (7)
S2^iv—Gd1—S1	68.57 (5)	S1^vi—Sn1—S1^ix	97.21 (7)
S3—Gd1—S2	72.21 (3)	S1^vii—Sn1—S2^x	94.37 (5)
S3^i—Gd1—S2	126.17 (4)	S1^viii—Sn1—S2^x	94.37 (5)
S1^ii—Gd1—S2	69.03 (5)	S1^vi—Sn1—S2^x	85.63 (5)
S2^iii—Gd1—S2	142.99 (3)	S1^ix—Sn1—S2^x	85.63 (5)
S2^iv—Gd1—S2	87.32 (2)	S1^vii—Sn1—S2	85.63 (5)
S1—Gd1—S2	138.58 (3)	S1^viii—Sn1—S2	85.63 (5)
S3—Gd1—S2^i	126.17 (4)	S1^vi—Sn1—S2	94.37 (5)
S3^i—Gd1—S2^i	72.21 (3)	S1^ix—Sn1—S2	94.37 (5)
S1^ii—Gd1—S2^i	69.03 (5)	S2^x—Sn1—S2	180.00 (8)
S2^iii—Gd1—S2^i	87.32 (2)	Sn1^xi—S1—Sn1^xii	97.21 (7)
S2^iv—Gd1—S2^i	142.99 (3)	Sn1^xi—S1—Gd1^iv	100.53 (5)
S1—Gd1—S2^i	138.58 (3)	Sn1^xii—S1—Gd1^iv	100.53 (5)
S2—Gd1—S2^i	80.08 (5)	Sn1^xi—S1—Gd1	128.62 (4)
S3—Gd1—Gd1^v	45.870 (11)	Sn1^xii—S1—Gd1	128.62 (4)
S3^i—Gd1—Gd1^v	134.130 (11)	Gd1^iv—S1—Gd1	93.22 (6)
S1^ii—Gd1—Gd1^v	90.0	Sn1—S2—Gd1^ii	99.05 (5)
S2^iii—Gd1—Gd1^v	131.08 (3)	Sn1—S2—Gd1^xiii	99.05 (5)
S2^iv—Gd1—Gd1^v	48.92 (3)	Gd1^ii—S2—Gd1^xiii	82.15 (5)
S1—Gd1—Gd1^v	90.0	Sn1—S2—Gd1	108.37 (6)
S2—Gd1—Gd1^v	49.96 (2)	Gd1^ii—S2—Gd1	92.41 (3)
S2^i—Gd1—Gd1^v	130.04 (3)	Gd1^xiii—S2—Gd1	152.56 (7)
S3—Gd1—Gd1^i	134.130 (11)	Sn1—S2—Gd1^v	108.37 (6)
S3^i—Gd1—Gd1^i	45.870 (11)	Gd1^ii—S2—Gd1^v	152.56 (7)
S1^ii—Gd1—Gd1^i	90.0	Gd1^xiii—S2—Gd1^v	92.41 (3)
S2^iii—Gd1—Gd1^i	48.92 (3)	Gd1—S2—Gd1^v	80.08 (5)
S2^iv—Gd1—Gd1^i	131.08 (3)	Gd1—S3—Gd1^ix	180.000 (12)
S1—Gd1—Gd1^i	90.0	Gd1—S3—Gd1^v	88.26 (2)
S2—Gd1—Gd1^i	130.04 (2)	Gd1^ix—S3—Gd1^v	91.74 (2)
S2^i—Gd1—Gd1^i	49.96 (2)	Gd1—S3—Gd1^vi	91.74 (2)
Gd1^v—Gd1—Gd1^i	180.000 (17)	Gd1^ix—S3—Gd1^vi	88.26 (2)
S3—Gd1—Gd1^vi	44.130 (11)	Gd1^v—S3—Gd1^vi	180.000 (12)

Symmetry codes: (i) x, y, z+1; (ii) x−1/2, −y+1/2, z; (iii) x+1/2, −y+1/2, z+1; (iv) x+1/2, −y+1/2, z; (v) x, y, z−1; (vi) −x+1, −y, −z+1; (vii) x−1, y, z−1; (viii) x−1, y, z; (ix) −x+1, −y, −z; (x) −x, −y, −z; (xi) x+1, y, z+1; (xii) x+1, y, z; (xiii) x−1/2, −y+1/2, z−1.

(tb)

Crystal data

S5SnTb2	F(000) = 520
Mr = 596.83	Dx = 6.002 Mg m^−3
Orthorhombic, Pbam	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2 2ab	Cell parameters from 436 reflections
a = 7.717 (2) Å	θ = 3.6–28.3°
b = 11.2460 (15) Å	µ = 26.38 mm^−1
c = 3.8056 (8) Å	T = 293 K
V = 330.27 (13) Å^3	Prism, black
Z = 2	0.11 × 0.06 × 0.03 mm

Data collection

KUMA KM-4 with area CCD detector diffractometer	467 independent reflections
Radiation source: fine-focus sealed tube	436 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.042
Detector resolution: 1024x1024 with blocks 2x2, 33.133pixel/mm pixels mm^-1	θmax = 28.3°, θmin = 3.6°
ω–scan	h = −10→9
Absorption correction: numerical M. Mayer, CrysAlis Data Reduction Program, Oxford Diffraction Ltd, 2007	k = −14→14
Tmin = 0.155, Tmax = 0.422	l = −5→5
4139 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.016	w = 1/[σ^2(Fo^2) + (0.0124P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.028	(Δ/σ)max < 0.001
S = 1.04	Δρmax = 0.95 e Å^−3
467 reflections	Δρmin = −1.06 e Å^−3
28 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0076 (3)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Tb1	0.46598 (3)	0.17285 (2)	0.5000	0.00959 (9)
Sn2	0.0000	0.0000	0.0000	0.00902 (12)
S1	0.82826 (17)	0.09314 (10)	0.5000	0.0098 (2)
S2	0.17306 (17)	0.19510 (9)	0.0000	0.0095 (2)
S3	0.5000	0.0000	0.0000	0.0100 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Tb1	0.01379 (15)	0.00798 (13)	0.00699 (13)	0.00089 (9)	0.000	0.000
Sn2	0.0134 (3)	0.0072 (2)	0.0065 (2)	−0.00044 (17)	0.000	0.000
S1	0.0104 (6)	0.0105 (5)	0.0084 (6)	0.0019 (5)	0.000	0.000
S2	0.0108 (6)	0.0084 (5)	0.0094 (6)	−0.0007 (4)	0.000	0.000
S3	0.0138 (10)	0.0080 (7)	0.0081 (8)	0.0001 (6)	0.000	0.000

Geometric parameters (Å, º)

Tb1—S3	2.7328 (4)	Sn2—S1^vi	2.5445 (9)
Tb1—S3^i	2.7328 (4)	Sn2—S1^ix	2.5445 (9)
Tb1—S1^ii	2.8381 (12)	Sn2—S2^x	2.5686 (12)
Tb1—S2^iii	2.8948 (10)	Sn2—S2	2.5686 (12)
Tb1—S2^iv	2.8948 (10)	S1—Sn2^xi	2.5445 (9)
Tb1—S1	2.9359 (15)	S1—Sn2^xii	2.5445 (9)
Tb1—S2	2.9653 (12)	S1—Tb1^iv	2.8381 (12)
Tb1—S2^i	2.9653 (12)	S2—Tb1^ii	2.8948 (10)
Tb1—Tb1^v	3.8056 (8)	S2—Tb1^xiii	2.8948 (10)
Tb1—Tb1^i	3.8056 (8)	S2—Tb1^v	2.9653 (12)
Tb1—Tb1^vi	3.9231 (7)	S3—Tb1^ix	2.7328 (4)
Sn2—S1^vii	2.5445 (9)	S3—Tb1^vi	2.7328 (4)
Sn2—S1^viii	2.5445 (9)	S3—Tb1^v	2.7328 (4)
S3—Tb1—S3^i	88.258 (16)	S3^i—Tb1—Tb1^vi	44.129 (8)
S3—Tb1—S1^ii	134.069 (10)	S1^ii—Tb1—Tb1^vi	165.70 (3)
S3^i—Tb1—S1^ii	134.069 (10)	S2^iii—Tb1—Tb1^vi	115.75 (2)
S3—Tb1—S2^iii	140.31 (3)	S2^iv—Tb1—Tb1^vi	115.75 (2)
S3^i—Tb1—S2^iii	81.62 (2)	S1—Tb1—Tb1^vi	64.53 (2)
S1^ii—Tb1—S2^iii	74.40 (3)	S2—Tb1—Tb1^vi	100.70 (2)
S3—Tb1—S2^iv	81.62 (2)	S2^i—Tb1—Tb1^vi	100.70 (2)
S3^i—Tb1—S2^iv	140.31 (3)	Tb1^v—Tb1—Tb1^vi	90.0
S1^ii—Tb1—S2^iv	74.40 (3)	Tb1^i—Tb1—Tb1^vi	90.0
S2^iii—Tb1—S2^iv	82.19 (4)	S1^vii—Sn2—S1^viii	96.80 (4)
S3—Tb1—S1	72.021 (17)	S1^vii—Sn2—S1^vi	180.00 (5)
S3^i—Tb1—S1	72.021 (17)	S1^viii—Sn2—S1^vi	83.20 (4)
S1^ii—Tb1—S1	129.77 (4)	S1^vii—Sn2—S1^ix	83.20 (4)
S2^iii—Tb1—S1	68.34 (3)	S1^viii—Sn2—S1^ix	180.0
S2^iv—Tb1—S1	68.34 (3)	S1^vi—Sn2—S1^ix	96.80 (4)
S3—Tb1—S2	71.73 (2)	S1^vii—Sn2—S2^x	94.64 (4)
S3^i—Tb1—S2	125.45 (2)	S1^viii—Sn2—S2^x	94.64 (4)
S1^ii—Tb1—S2	68.67 (3)	S1^vi—Sn2—S2^x	85.36 (4)
S2^iii—Tb1—S2	143.07 (2)	S1^ix—Sn2—S2^x	85.36 (4)
S2^iv—Tb1—S2	87.46 (2)	S1^vii—Sn2—S2	85.36 (4)
S1—Tb1—S2	138.73 (2)	S1^viii—Sn2—S2	85.36 (4)
S3—Tb1—S2^i	125.45 (2)	S1^vi—Sn2—S2	94.64 (4)
S3^i—Tb1—S2^i	71.73 (2)	S1^ix—Sn2—S2	94.64 (4)
S1^ii—Tb1—S2^i	68.67 (3)	S2^x—Sn2—S2	180.00 (2)
S2^iii—Tb1—S2^i	87.46 (2)	Sn2^xi—S1—Sn2^xii	96.80 (4)
S2^iv—Tb1—S2^i	143.07 (2)	Sn2^xi—S1—Tb1^iv	100.76 (4)
S1—Tb1—S2^i	138.73 (2)	Sn2^xii—S1—Tb1^iv	100.76 (4)
S2—Tb1—S2^i	79.84 (4)	Sn2^xi—S1—Tb1	128.44 (3)
S3—Tb1—Tb1^v	45.871 (8)	Sn2^xii—S1—Tb1	128.44 (3)
S3^i—Tb1—Tb1^v	134.129 (8)	Tb1^iv—S1—Tb1	94.21 (4)
S1^ii—Tb1—Tb1^v	90.0	Sn2—S2—Tb1^ii	98.70 (4)
S2^iii—Tb1—Tb1^v	131.096 (18)	Sn2—S2—Tb1^xiii	98.70 (4)
S2^iv—Tb1—Tb1^v	48.904 (18)	Tb1^ii—S2—Tb1^xiii	82.19 (4)
S1—Tb1—Tb1^v	90.0	Sn2—S2—Tb1	108.92 (3)
S2—Tb1—Tb1^v	50.08 (2)	Tb1^ii—S2—Tb1	92.42 (2)
S2^i—Tb1—Tb1^v	129.92 (2)	Tb1^xiii—S2—Tb1	152.36 (4)
S3—Tb1—Tb1^i	134.129 (8)	Sn2—S2—Tb1^v	108.92 (3)
S3^i—Tb1—Tb1^i	45.871 (8)	Tb1^ii—S2—Tb1^v	152.36 (4)
S1^ii—Tb1—Tb1^i	90.0	Tb1^xiii—S2—Tb1^v	92.42 (2)
S2^iii—Tb1—Tb1^i	48.904 (18)	Tb1—S2—Tb1^v	79.84 (4)
S2^iv—Tb1—Tb1^i	131.096 (18)	Tb1^ix—S3—Tb1	180.000 (11)
S1—Tb1—Tb1^i	90.0	Tb1^ix—S3—Tb1^vi	88.258 (16)
S2—Tb1—Tb1^i	129.92 (2)	Tb1—S3—Tb1^vi	91.742 (16)
S2^i—Tb1—Tb1^i	50.08 (2)	Tb1^ix—S3—Tb1^v	91.742 (16)
Tb1^v—Tb1—Tb1^i	180.000 (17)	Tb1—S3—Tb1^v	88.258 (16)
S3—Tb1—Tb1^vi	44.129 (8)	Tb1^vi—S3—Tb1^v	180.000 (12)

Symmetry codes: (i) x, y, z+1; (ii) x−1/2, −y+1/2, z; (iii) x+1/2, −y+1/2, z+1; (iv) x+1/2, −y+1/2, z; (v) x, y, z−1; (vi) −x+1, −y, −z+1; (vii) x−1, y, z−1; (viii) x−1, y, z; (ix) −x+1, −y, −z; (x) −x, −y, −z; (xi) x+1, y, z+1; (xii) x+1, y, z; (xiii) x−1/2, −y+1/2, z−1.