Structure determination of KScS₂, RbScS₂ and KLnS₂ (Ln = Nd, Sm, Tb, Dy, Ho, Er, Tm and Yb) and crystal–chemical discussion

The title structures of KScS₂ (potassium scandium sulfide), RbScS₂ (rubidium scandium sulfide) and KLnS₂ [Ln = Nd (potassium neodymium sufide), Sm (potassium samarium sulfide), Tb (potassium terbium sulfide), Dy (potassium dysprosium sulfide), Ho (potassium holmium sulfide), Er (potassium erbium sulfide), Tm (potassium thulium sulfide) and Yb (potassium ytterbium sulfide)] are either newly determined (KScS₂, RbScS₂ and KTbS₂) or redetermined. All of them belong to the α-NaFeO₂ structure type in agreement with the ratio of the ionic radii r³⁺/r⁺. KScS₂, the member of this structural family with the smallest trivalent cation, is an extreme representative of these structures with rare earth trivalent cations. The title structures are compared with isostructural alkali rare earth sulfides in plots showing the dependence of several relevant parameters on the trivalent cation crystal radius; the parameters thus compared are c, a and c/a, the thicknesses of the S—S layers which contain the respective constituent cations, the sulfur fractional coordinates z(S²⁻) and the bond-valence sums.

Computing details

For all compounds, data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007); program(s) used to refine structure: JANA2006 (Petříček et al., 2014). Molecular graphics: Brandenburg & Putz (2005) for (II). For all compounds, software used to prepare material for publication: JANA2006 (Petříček et al., 2014).

(I) Potassium scandium sulfide

Crystal data

KScS2	Dx = 2.703 Mg m^−3
Mr = 148.2	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 936 reflections
Hall symbol: -R 3 2"	θ = 5.6–28.8°
a = 3.8106 (3) Å	µ = 4.04 mm^−1
c = 21.719 (2) Å	T = 292 K
V = 273.12 (4) Å^3	Plate, yellow
Z = 3	0.46 × 0.27 × 0.05 mm
F(000) = 216

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	119 independent reflections
Radiation source: X-ray tube	106 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.052
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.2°, θmin = 5.6°
ω scans	h = −5→5
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −5→5
Tmin = 0.347, Tmax = 0.832	l = −28→29
1277 measured reflections

Refinement

Refinement on F^2	0 restraints
R[F > 3σ(F)] = 0.025	0 constraints
wR(F) = 0.064	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
S = 1.92	(Δ/σ)max = 0.002
119 reflections	Δρmax = 0.48 e Å^−3
8 parameters	Δρmin = −0.53 e Å^−3

Special details

Refinement. Refinement of a model with obverse–reverse twinning turned out to be insignificant.

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0124 (5)
Sc	0.333333	0.666667	0.166667	0.0062 (4)
S	0	0	0.23113 (6)	0.0067 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0139 (6)	0.0139 (6)	0.0094 (9)	0.0069 (3)	0	0
Sc	0.0058 (5)	0.0058 (5)	0.0068 (7)	0.0029 (2)	0	0
S	0.0066 (4)	0.0066 (4)	0.0068 (7)	0.0033 (2)	0	0

Geometric parameters (Å, º)

K—K^i	3.8106 (9)	Sc—Sc^vi	3.8106 (9)
K—K^ii	3.8106 (6)	Sc—S	2.6078 (8)
K—K^iii	3.8106 (6)	Sc—S^iv	2.6078 (8)
K—K^iv	3.8106 (6)	Sc—S^vi	2.6078 (8)
K—K^v	3.8106 (6)	Sc—S^xi	2.6078 (8)
K—K^vi	3.8106 (9)	Sc—S^xii	2.6078 (8)
K—S^vii	3.1253 (11)	Sc—S^xiii	2.6078 (8)
K—S^viii	3.1253 (10)	S—S^i	3.8106 (9)
K—S^ix	3.1253 (11)	S—S^ii	3.8106 (6)
K—S^x	3.1253 (11)	S—S^iii	3.8106 (6)
K—S^xi	3.1253 (10)	S—S^iv	3.8106 (6)
K—S^xii	3.1253 (11)	S—S^v	3.8106 (6)
Sc—Sc^i	3.8106 (9)	S—S^vi	3.8106 (9)
Sc—Sc^ii	3.8106 (6)	S—S^x	3.5611 (16)
Sc—Sc^iii	3.8106 (6)	S—S^xi	3.5611 (16)
Sc—Sc^iv	3.8106 (6)	S—S^xii	3.5611 (16)
Sc—Sc^v	3.8106 (6)
S—Sc—S^iv	93.88 (2)	S^vi—Sc—S^xiii	86.12 (3)
S—Sc—S^vi	93.88 (3)	S^xi—Sc—S^xii	93.88 (2)
S—Sc—S^xi	86.12 (3)	S^xi—Sc—S^xiii	93.88 (3)
S—Sc—S^xii	86.12 (2)	S^xii—Sc—S^xiii	93.88 (2)
S—Sc—S^xiii	180.0 (5)	K^xiv—S—K^xv	75.13 (3)
S^iv—Sc—S^vi	93.88 (2)	K^xiv—S—K^xvi	75.13 (3)
S^iv—Sc—S^xi	86.12 (2)	K^xv—S—K^xvi	75.13 (3)
S^iv—Sc—S^xii	180.0 (5)	Sc^i—S—Sc^iii	93.88 (3)
S^iv—Sc—S^xiii	86.12 (2)	Sc^i—S—Sc	93.88 (3)
S^vi—Sc—S^xi	180.0 (5)	Sc^iii—S—Sc	93.88 (3)
S^vi—Sc—S^xii	86.12 (2)

Symmetry codes: (i) x−1, y−1, z; (ii) x−1, y, z; (iii) x, y−1, z; (iv) x, y+1, z; (v) x+1, y, z; (vi) x+1, y+1, z; (vii) x−2/3, y−1/3, z−1/3; (viii) x+1/3, y−1/3, z−1/3; (ix) x+1/3, y+2/3, z−1/3; (x) y−1/3, x−2/3, −z+1/3; (xi) y−1/3, x+1/3, −z+1/3; (xii) y+2/3, x+1/3, −z+1/3; (xiii) y+2/3, x+4/3, −z+1/3; (xiv) x−1/3, y−2/3, z+1/3; (xv) x−1/3, y+1/3, z+1/3; (xvi) x+2/3, y+1/3, z+1/3.

(II) Rubidium scandium sulfide

Crystal data

RbScS2	Dx = 3.367 Mg m^−3
Mr = 194.5	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 539 reflections
Hall symbol: -R 3 2"	θ = 5.4–28.9°
a = 3.8299 (6) Å	µ = 15.35 mm^−1
c = 22.656 (3) Å	T = 293 K
V = 287.80 (7) Å^3	Plate, yellow–green
Z = 3	0.17 × 0.14 × 0.04 mm
F(000) = 270

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	120 independent reflections
Radiation source: X-ray tube	118 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.069
Detector resolution: 5.1873 pixels mm^-1	θmax = 28.9°, θmin = 5.4°
ω scans	h = −5→3
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −3→5
Tmin = 0.173, Tmax = 0.609	l = −25→30
611 measured reflections

Refinement

Refinement on F^2	0 restraints
R[F > 3σ(F)] = 0.033	0 constraints
wR(F) = 0.068	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
S = 1.86	(Δ/σ)max = 0.004
120 reflections	Δρmax = 0.82 e Å^−3
8 parameters	Δρmin = −0.97 e Å^−3

Special details

Refinement. Refinement of a model with obverse–reverse twinning turned out to be insignificant.

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

	x	y	z	Uiso*/Ueq
Rb	0	0	0	0.0145 (4)
Sc	0.333333	0.666667	0.166667	0.0070 (6)
S	0	0	0.22811 (10)	0.0073 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Rb	0.0155 (5)	0.0155 (5)	0.0125 (7)	0.0078 (2)	0	0
Sc	0.0065 (6)	0.0065 (6)	0.0080 (11)	0.0032 (3)	0	0
S	0.0072 (6)	0.0072 (6)	0.0075 (10)	0.0036 (3)	0	0

Geometric parameters (Å, º)

Rb—S^i	3.2515 (18)	Sc—S^ix	2.6129 (14)
Rb—S^ii	3.2515 (17)	S—S^x	3.8299 (18)
Rb—S^iii	3.2515 (18)	S—S^xi	3.8299 (12)
Rb—S^iv	3.2515 (18)	S—S^xii	3.8299 (12)
Rb—S^v	3.2515 (17)	S—S^vii	3.8299 (12)
Rb—S^vi	3.2515 (18)	S—S^xiii	3.8299 (12)
Sc—S	2.6129 (14)	S—S^viii	3.8299 (18)
Sc—S^vii	2.6129 (12)	S—S^iv	3.555 (3)
Sc—S^viii	2.6129 (14)	S—S^v	3.555 (3)
Sc—S^v	2.6129 (14)	S—S^vi	3.555 (3)
Sc—S^vi	2.6129 (12)
S^i—Rb—S^ii	72.16 (3)	S—Sc—S^vi	85.74 (4)
S^i—Rb—S^iii	72.16 (3)	S—Sc—S^ix	180.0 (5)
S^i—Rb—S^iv	107.84 (3)	S^vii—Sc—S^viii	94.26 (4)
S^i—Rb—S^v	107.84 (3)	S^vii—Sc—S^v	85.74 (4)
S^i—Rb—S^vi	180.0 (5)	S^vii—Sc—S^vi	180.0 (5)
S^ii—Rb—S^iii	72.16 (3)	S^vii—Sc—S^ix	85.74 (4)
S^ii—Rb—S^iv	107.84 (3)	S^viii—Sc—S^v	180.0 (5)
S^ii—Rb—S^v	180.0 (5)	S^viii—Sc—S^vi	85.74 (4)
S^ii—Rb—S^vi	107.84 (3)	S^viii—Sc—S^ix	85.74 (4)
S^iii—Rb—S^iv	180.0 (5)	S^v—Sc—S^vi	94.26 (4)
S^iii—Rb—S^v	107.84 (3)	S^v—Sc—S^ix	94.26 (4)
S^iii—Rb—S^vi	107.84 (3)	S^vi—Sc—S^ix	94.26 (4)
S^iv—Rb—S^v	72.16 (3)	Rb^xiv—S—Rb^xv	72.16 (4)
S^iv—Rb—S^vi	72.16 (3)	Rb^xiv—S—Rb^xvi	72.16 (4)
S^v—Rb—S^vi	72.16 (3)	Rb^xv—S—Rb^xvi	72.16 (4)
S—Sc—S^vii	94.26 (4)	Sc^x—S—Sc^xii	94.26 (6)
S—Sc—S^viii	94.26 (4)	Sc^x—S—Sc	94.26 (6)
S—Sc—S^v	85.74 (4)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1, y−1, z; (xi) x−1, y, z; (xii) x, y−1, z; (xiii) x+1, y, z; (xiv) x−1/3, y−2/3, z+1/3; (xv) x−1/3, y+1/3, z+1/3; (xvi) x+2/3, y+1/3, z+1/3.

(III) Potassium neodymium sufide

Crystal data

KNdS2	Dx = 3.75 Mg m^−3
Mr = 247.5	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 1587 reflections
Hall symbol: -R 3 2"	θ = 5.6–29.4°
a = 4.1626 (3) Å	µ = 13.52 mm^−1
c = 21.8996 (19) Å	T = 301 K
V = 328.62 (5) Å^3	Plate, blue
Z = 3	0.14 × 0.13 × 0.05 mm
F(000) = 333

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	140 independent reflections
Radiation source: X-ray tube	140 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.036
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.5°, θmin = 5.6°
w/2q scans	h = −5→5
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −5→5
Tmin = 0.258, Tmax = 0.544	l = −29→27
1538 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.010	Weighting scheme based on measured s.u.'s w = 1/[σ^2(F) + 0.0001F^2]
wR(F) = 0.010	(Δ/σ)max = 0.002
S = 0.60	Δρmax = 0.17 e Å^−3
140 reflections	Δρmin = −0.09 e Å^−3
9 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 160 (40)

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0150 (3)
Nd	0.333333	0.666667	0.166667	0.00774 (10)
S	0	0	0.23595 (4)	0.0088 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0160 (3)	0.0160 (3)	0.0131 (5)	0.00800 (17)	0	0
Nd	0.00639 (13)	0.00639 (13)	0.01047 (16)	0.00320 (6)	0	0
S	0.0082 (2)	0.0082 (2)	0.0101 (4)	0.00409 (13)	0	0

Geometric parameters (Å, º)

K—S^i	3.2132 (8)	Nd—S^viii	2.8421 (7)
K—S^ii	3.2132 (7)	Nd—S^v	2.8421 (7)
K—S^iii	3.2132 (8)	Nd—S^vi	2.8421 (5)
K—S^iv	3.2132 (8)	Nd—S^ix	2.8421 (7)
K—S^v	3.2132 (7)	S—S^iv	3.8708 (12)
K—S^vi	3.2132 (8)	S—S^v	3.8708 (11)
Nd—S	2.8421 (7)	S—S^vi	3.8708 (12)
Nd—S^vii	2.8421 (5)
S^i—K—S^ii	80.743 (14)	S^vii—Nd—S^viii	94.161 (16)
S^i—K—S^iii	80.743 (16)	S^vii—Nd—S^v	85.839 (16)
S^i—K—S^iv	99.257 (16)	S^vii—Nd—S^vi	180
S^i—K—S^v	99.257 (14)	S^vii—Nd—S^ix	85.839 (16)
S^i—K—S^vi	180	S^viii—Nd—S^v	180
S^ii—K—S^iii	80.743 (14)	S^viii—Nd—S^vi	85.839 (16)
S^ii—K—S^iv	99.257 (14)	S^viii—Nd—S^ix	85.839 (17)
S^ii—K—S^v	180	S^v—Nd—S^vi	94.161 (16)
S^ii—K—S^vi	99.257 (14)	S^v—Nd—S^ix	94.161 (17)
S^iii—K—S^iv	180	S^vi—Nd—S^ix	94.161 (16)
S^iii—K—S^v	99.257 (14)	K^x—S—K^xi	80.743 (19)
S^iii—K—S^vi	99.257 (16)	K^x—S—K^xii	80.74 (2)
S^iv—K—S^v	80.743 (14)	K^xi—S—K^xii	80.743 (19)
S^iv—K—S^vi	80.743 (16)	K^xi—S—Nd^xiii	92.183 (7)
S^v—K—S^vi	80.743 (14)	K^xi—S—Nd^xiv	170.68 (3)
S—Nd—S^vii	94.161 (16)	K^xi—S—Nd	92.183 (7)
S—Nd—S^viii	94.161 (17)	Nd^xiii—S—Nd^xiv	94.16 (2)
S—Nd—S^v	85.839 (17)	Nd^xiii—S—Nd	94.16 (2)
S—Nd—S^vi	85.839 (16)	Nd^xiv—S—Nd	94.16 (2)
S—Nd—S^ix	180

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(IV) Potassium samarium sulfide

Crystal data

KSmS2	Dx = 3.931 Mg m^−3
Mr = 253.6	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 646 reflections
Hall symbol: -R 3 2"	θ = 5.6–28.9°
a = 4.1174 (6) Å	µ = 15.42 mm^−1
c = 21.888 (3) Å	T = 293 K
V = 321.35 (8) Å^3	Plate, yellow
Z = 3	0.20 × 0.14 × 0.03 mm
F(000) = 339

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	135 independent reflections
Radiation source: X-ray tube	135 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.086
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.0°, θmin = 5.6°
ω scans	h = −5→5
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −4→5
Tmin = 0.227, Tmax = 0.672	l = −28→25
721 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.031	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
wR(F) = 0.069	(Δ/σ)max = 0.001
S = 1.86	Δρmax = 1.48 e Å^−3
135 reflections	Δρmin = −1.79 e Å^−3
9 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 470 (150)

Special details

Refinement. Refinement of a model with obverse-reverse twinning turned out to be insignificant.

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0153 (11)
Sm	0.333333	0.666667	0.166667	0.0073 (4)
S	0	0	0.23520 (16)	0.0087 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0174 (13)	0.0174 (13)	0.011 (2)	0.0087 (7)	0	0
Sm	0.0062 (5)	0.0062 (5)	0.0096 (6)	0.0031 (2)	0	0
S	0.0092 (10)	0.0092 (10)	0.0076 (15)	0.0046 (5)	0	0

Geometric parameters (Å, º)

K—S^i	3.204 (2)	Sm—S	2.811 (2)
K—S^ii	3.204 (2)	Sm—S^vii	2.8109 (18)
K—S^iii	3.204 (2)	Sm—S^viii	2.811 (2)
K—S^iv	3.204 (2)	Sm—S^v	2.811 (2)
K—S^v	3.204 (2)	Sm—S^vi	2.8109 (18)
K—S^vi	3.204 (2)	Sm—S^ix	2.811 (2)
S^i—K—S^ii	79.97 (5)	S—Sm—S^vi	85.82 (6)
S^i—K—S^iii	79.97 (5)	S—Sm—S^ix	180.0 (5)
S^i—K—S^iv	100.03 (5)	S^vii—Sm—S^viii	94.18 (6)
S^i—K—S^v	100.03 (5)	S^vii—Sm—S^v	85.82 (6)
S^i—K—S^vi	180.0 (5)	S^vii—Sm—S^vi	180.0 (5)
S^ii—K—S^iii	79.97 (5)	S^vii—Sm—S^ix	85.82 (6)
S^ii—K—S^iv	100.03 (5)	S^viii—Sm—S^v	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^viii—Sm—S^vi	85.82 (6)
S^ii—K—S^vi	100.03 (5)	S^viii—Sm—S^ix	85.82 (6)
S^iii—K—S^iv	180.0 (5)	S^v—Sm—S^vi	94.17 (6)
S^iii—K—S^v	100.03 (5)	S^v—Sm—S^ix	94.18 (6)
S^iii—K—S^vi	100.03 (5)	S^vi—Sm—S^ix	94.17 (6)
S^iv—K—S^v	79.97 (5)	K^x—S—K^xi	79.97 (7)
S^iv—K—S^vi	79.97 (5)	K^x—S—K^xii	79.97 (7)
S^v—K—S^vi	79.97 (5)	K^xi—S—K^xii	79.97 (7)
S—Sm—S^vii	94.18 (6)	Sm^xiii—S—Sm^xiv	94.18 (8)
S—Sm—S^viii	94.18 (6)	Sm^xiii—S—Sm	94.18 (8)
S—Sm—S^v	85.82 (6)	Sm^xiv—S—Sm	94.18 (8)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(V) Potassium terbium sulfide

Crystal data

KTbS2	Dx = 4.196 Mg m^−3
Mr = 262.1	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 597 reflections
Hall symbol: -R 3 2"	θ = 5.6–28.7°
a = 4.0523 (7) Å	µ = 18.81 mm^−1
c = 21.885 (3) Å	T = 295 K
V = 311.23 (9) Å^3	Prism, white
Z = 3	0.20 × 0.08 × 0.05 mm
F(000) = 348

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	129 independent reflections
Radiation source: X-ray tube	129 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.061
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.3°, θmin = 5.6°
ω scans	h = −5→4
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −5→5
Tmin = 0.238, Tmax = 0.447	l = −26→27
674 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.017	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
wR(F) = 0.035	(Δ/σ)max = 0.003
S = 0.97	Δρmax = 0.45 e Å^−3
129 reflections	Δρmin = −0.64 e Å^−3
9 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 1570 (120)

Special details

Refinement. Refinement of a model with obverse–reverse twinning turned out to be insignificant.

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0149 (6)
Tb	0.333333	0.666667	0.166667	0.0076 (2)
S	0	0	0.23463 (9)	0.0086 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0172 (7)	0.0172 (7)	0.0103 (11)	0.0086 (4)	0	0
Tb	0.0067 (3)	0.0067 (3)	0.0094 (3)	0.00334 (14)	0	0
S	0.0084 (5)	0.0084 (5)	0.0091 (8)	0.0042 (3)	0	0

Geometric parameters (Å, º)

K—S^i	3.1844 (16)	Tb—S	2.7723 (14)
K—S^ii	3.1844 (14)	Tb—S^vii	2.7723 (11)
K—S^iii	3.1844 (16)	Tb—S^viii	2.7723 (14)
K—S^iv	3.1844 (16)	Tb—S^v	2.7723 (14)
K—S^v	3.1844 (14)	Tb—S^vi	2.7723 (11)
K—S^vi	3.1844 (16)	Tb—S^ix	2.7723 (14)
S^i—K—S^ii	79.03 (3)	S—Tb—S^vi	86.08 (3)
S^i—K—S^iii	79.03 (3)	S—Tb—S^ix	180.0 (5)
S^i—K—S^iv	100.97 (3)	S^vii—Tb—S^viii	93.92 (3)
S^i—K—S^v	100.97 (3)	S^vii—Tb—S^v	86.08 (3)
S^i—K—S^vi	180.0 (5)	S^vii—Tb—S^vi	180.0 (5)
S^ii—K—S^iii	79.03 (3)	S^vii—Tb—S^ix	86.08 (3)
S^ii—K—S^iv	100.97 (3)	S^viii—Tb—S^v	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^viii—Tb—S^vi	86.08 (3)
S^ii—K—S^vi	100.97 (3)	S^viii—Tb—S^ix	86.08 (4)
S^iii—K—S^iv	180.0 (5)	S^v—Tb—S^vi	93.92 (3)
S^iii—K—S^v	100.97 (3)	S^v—Tb—S^ix	93.92 (4)
S^iii—K—S^vi	100.97 (3)	S^vi—Tb—S^ix	93.92 (3)
S^iv—K—S^v	79.03 (3)	K^x—S—K^xi	79.03 (4)
S^iv—K—S^vi	79.03 (3)	K^x—S—K^xii	79.03 (4)
S^v—K—S^vi	79.03 (3)	K^xi—S—K^xii	79.03 (4)
S—Tb—S^vii	93.92 (3)	Tb^xiii—S—Tb^xiv	93.92 (5)
S—Tb—S^viii	93.92 (4)	Tb^xiii—S—Tb	93.92 (5)
S—Tb—S^v	86.08 (4)	Tb^xiv—S—Tb	93.92 (5)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(VI) Potassium dysprosium sulfide

Crystal data

KDyS2	Dx = 4.296 Mg m^−3
Mr = 265.7	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 386 reflections
Hall symbol: -R 3 2"	θ = 5.9–28.6°
a = 4.0315 (11) Å	µ = 19.97 mm^−1
c = 21.890 (5) Å	T = 294 K
V = 308.11 (14) Å^3	Block, white
Z = 3	0.21 × 0.09 × 0.03 mm
F(000) = 351

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	126 independent reflections
Radiation source: X-ray tube	124 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.100
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.3°, θmin = 5.6°
ω scans	h = −5→4
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −3→5
Tmin = 0.201, Tmax = 0.703	l = −25→27
658 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.052	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
wR(F) = 0.105	(Δ/σ)max = 0.001
S = 2.32	Δρmax = 4.44 e Å^−3
126 reflections	Δρmin = −2.46 e Å^−3
9 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 1900 (400)

Special details

Refinement. A model with inclusion of obverse–reverse twinning turned out to be insignificant.

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.022 (3)
Dy	0.333333	0.666667	0.166667	0.0137 (8)
S	0	0	0.2345 (3)	0.0138 (19)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.020 (3)	0.020 (3)	0.025 (5)	0.0099 (14)	0	0
Dy	0.0106 (9)	0.0106 (9)	0.0199 (13)	0.0053 (5)	0	0
S	0.011 (2)	0.011 (2)	0.019 (4)	0.0057 (10)	0	0

Geometric parameters (Å, º)

K—S^i	3.179 (5)	Dy—S^viii	2.760 (4)
K—S^ii	3.179 (5)	Dy—S^v	2.760 (4)
K—S^iii	3.179 (5)	Dy—S^vi	2.760 (4)
K—S^iv	3.179 (5)	Dy—S^ix	2.760 (4)
K—S^v	3.179 (5)	S—S^iv	3.772 (8)
K—S^vi	3.179 (5)	S—S^v	3.772 (8)
Dy—S	2.760 (4)	S—S^vi	3.772 (8)
Dy—S^vii	2.760 (4)
S^i—K—S^ii	78.72 (11)	S—Dy—S^vi	86.18 (13)
S^i—K—S^iii	78.72 (11)	S—Dy—S^ix	180.0 (5)
S^i—K—S^iv	101.28 (11)	S^vii—Dy—S^viii	93.82 (13)
S^i—K—S^v	101.28 (11)	S^vii—Dy—S^v	86.18 (13)
S^i—K—S^vi	180.0 (5)	S^vii—Dy—S^vi	180.0 (5)
S^ii—K—S^iii	78.72 (11)	S^vii—Dy—S^ix	86.18 (13)
S^ii—K—S^iv	101.28 (11)	S^viii—Dy—S^v	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^viii—Dy—S^vi	86.18 (13)
S^ii—K—S^vi	101.28 (11)	S^viii—Dy—S^ix	86.18 (13)
S^iii—K—S^iv	180.0 (5)	S^v—Dy—S^vi	93.82 (13)
S^iii—K—S^v	101.28 (11)	S^v—Dy—S^ix	93.82 (13)
S^iii—K—S^vi	101.28 (11)	S^vi—Dy—S^ix	93.82 (13)
S^iv—K—S^v	78.72 (11)	K^x—S—K^xi	78.72 (15)
S^iv—K—S^vi	78.72 (11)	K^x—S—K^xii	78.72 (15)
S^v—K—S^vi	78.72 (11)	Dy^xiii—S—Dy^xiv	93.82 (18)
S—Dy—S^vii	93.82 (13)	Dy^xiii—S—Dy	93.82 (18)
S—Dy—S^viii	93.82 (13)	Dy^xiv—S—Dy	93.82 (18)
S—Dy—S^v	86.18 (13)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(VII) Potassium holmium sulfide

Crystal data

KHoS2	Dx = 4.385 Mg m^−3
Mr = 268.1	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 1327 reflections
Hall symbol: -R 3 2"	θ = 5.6–28.8°
a = 4.0098 (4) Å	µ = 21.29 mm^−1
c = 21.878 (2) Å	T = 303 K
V = 304.64 (5) Å^3	Prism, yellow
Z = 3	0.19 × 0.14 × 0.07 mm
F(000) = 354

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	216 independent reflections
Radiation source: X-ray tube	139 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.058
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.2°, θmin = 5.6°
ω scans	h = −5→5
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −5→5
Tmin = 0.090, Tmax = 0.243	l = −29→29
2289 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.020	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
wR(F) = 0.060	(Δ/σ)max = 0.002
S = 1.56	Δρmax = 0.77 e Å^−3
216 reflections	Δρmin = −1.00 e Å^−3
10 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 1410 (130)

Special details

Refinement. Obverse–reverse twinning has been applied, with the twinning matrix (-1 0 0 / 0 - 1 0 / 0 0 1). The domain-state proportions are 0.99986 (3) and 0.00014 (3).

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0156 (8)
Ho	0.333333	0.666667	0.166667	0.0077 (3)
S	0	0	0.23430 (11)	0.0091 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0180 (10)	0.0180 (10)	0.0108 (13)	0.0090 (5)	0	0
Ho	0.0078 (4)	0.0078 (4)	0.0074 (4)	0.00390 (18)	0	0
S	0.0105 (7)	0.0105 (7)	0.0063 (10)	0.0053 (4)	0	0

Geometric parameters (Å, º)

K—S^i	3.1708 (17)	Ho—S	2.7475 (14)
K—S^ii	3.1708 (17)	Ho—S^vii	2.7475 (13)
K—S^iii	3.1708 (17)	Ho—S^viii	2.7475 (14)
K—S^iv	3.1708 (17)	Ho—S^v	2.7475 (14)
K—S^v	3.1708 (17)	Ho—S^vi	2.7475 (13)
K—S^vi	3.1708 (17)	Ho—S^ix	2.7475 (14)
S^i—K—S^ii	78.44 (3)	S—Ho—S^vi	86.28 (4)
S^i—K—S^iii	78.44 (4)	S—Ho—S^ix	180.0 (5)
S^i—K—S^iv	101.56 (4)	S^vii—Ho—S^viii	93.73 (4)
S^i—K—S^v	101.56 (3)	S^vii—Ho—S^v	86.28 (4)
S^i—K—S^vi	180.0 (5)	S^vii—Ho—S^vi	180.0 (5)
S^ii—K—S^iii	78.44 (3)	S^vii—Ho—S^ix	86.28 (4)
S^ii—K—S^iv	101.56 (3)	S^viii—Ho—S^v	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^viii—Ho—S^vi	86.28 (4)
S^ii—K—S^vi	101.56 (3)	S^viii—Ho—S^ix	86.28 (4)
S^iii—K—S^iv	180.0 (5)	S^v—Ho—S^vi	93.72 (4)
S^iii—K—S^v	101.56 (3)	S^v—Ho—S^ix	93.72 (4)
S^iii—K—S^vi	101.56 (4)	S^vi—Ho—S^ix	93.72 (4)
S^iv—K—S^v	78.44 (3)	K^x—S—K^xi	78.44 (5)
S^iv—K—S^vi	78.44 (4)	K^x—S—K^xii	78.44 (5)
S^v—K—S^vi	78.44 (3)	K^xi—S—K^xii	78.44 (5)
S—Ho—S^vii	93.73 (4)	Ho^xiii—S—Ho^xiv	93.73 (6)
S—Ho—S^viii	93.73 (4)	Ho^xiii—S—Ho	93.73 (6)
S—Ho—S^v	86.28 (4)	Ho^xiv—S—Ho	93.73 (6)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(VIII) Potassium erbium sulfide

Crystal data

KErS2	Dx = 4.462 Mg m^−3
Mr = 270.5	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 1188 reflections
Hall symbol: -R 3 2"	θ = 5.6–28.9°
a = 3.9935 (4) Å	µ = 22.66 mm^−1
c = 21.866 (2) Å	T = 296 K
V = 302.00 (5) Å^3	Block, pink
Z = 3	0.08 × 0.07 × 0.05 mm
F(000) = 357

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	132 independent reflections
Radiation source: X-ray tube	132 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.070
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.1°, θmin = 2.8°
ω scans	h = −5→5
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −5→5
Tmin = 0.255, Tmax = 0.434	l = −29→28
1405 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.027	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
wR(F) = 0.064	(Δ/σ)max = 0.001
S = 1.81	Δρmax = 1.54 e Å^−3
132 reflections	Δρmin = −1.01 e Å^−3
9 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 770 (160)

Special details

Refinement. The refinement of a model with obverse–reverse twinning turned out to be insignificant

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0144 (13)
Er	0.333333	0.666667	0.166667	0.0074 (4)
S	0	0	0.23407 (17)	0.0078 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0138 (14)	0.0138 (14)	0.015 (2)	0.0069 (7)	0	0
Er	0.0058 (5)	0.0058 (5)	0.0105 (6)	0.0029 (2)	0	0
S	0.0075 (11)	0.0075 (11)	0.0082 (17)	0.0038 (5)	0	0

Geometric parameters (Å, º)

K—S^i	3.166 (3)	Er—S^viii	2.737 (2)
K—S^ii	3.166 (3)	Er—S^v	2.737 (2)
K—S^iii	3.166 (3)	Er—S^vi	2.737 (2)
K—S^iv	3.166 (3)	Er—S^ix	2.737 (2)
K—S^v	3.166 (3)	S—S^iv	3.742 (4)
K—S^vi	3.166 (3)	S—S^v	3.742 (4)
Er—S	2.737 (2)	S—S^vi	3.742 (4)
Er—S^vii	2.737 (2)
S^i—K—S^ii	78.19 (5)	S—Er—S^vi	86.28 (6)
S^i—K—S^iii	78.19 (5)	S—Er—S^ix	180.0 (5)
S^i—K—S^iv	101.81 (5)	S^vii—Er—S^viii	93.72 (6)
S^i—K—S^v	101.81 (5)	S^vii—Er—S^v	86.28 (6)
S^i—K—S^vi	180.0 (5)	S^vii—Er—S^vi	180.0 (5)
S^ii—K—S^iii	78.19 (5)	S^vii—Er—S^ix	86.28 (6)
S^ii—K—S^iv	101.81 (5)	S^viii—Er—S^v	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^viii—Er—S^vi	86.28 (6)
S^ii—K—S^vi	101.81 (5)	S^viii—Er—S^ix	86.28 (6)
S^iii—K—S^iv	180.0 (5)	S^v—Er—S^vi	93.72 (6)
S^iii—K—S^v	101.81 (5)	S^v—Er—S^ix	93.72 (6)
S^iii—K—S^vi	101.81 (5)	S^vi—Er—S^ix	93.72 (6)
S^iv—K—S^v	78.19 (5)	K^x—S—K^xi	78.19 (8)
S^iv—K—S^vi	78.19 (5)	K^x—S—K^xii	78.19 (8)
S^v—K—S^vi	78.19 (5)	K^xi—S—K^xii	78.19 (8)
S—Er—S^vii	93.72 (6)	Er^xiii—S—Er^xiv	93.72 (9)
S—Er—S^viii	93.72 (6)	Er^xiii—S—Er	93.72 (9)
S—Er—S^v	86.28 (6)	Er^xiv—S—Er	93.72 (9)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(IX) Potassium thulium sulfide

Crystal data

KTmS2	Dx = 4.534 Mg m^−3
Mr = 272.2	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 595 reflections
Hall symbol: -R 3 2"	θ = 5.6–29.1°
a = 3.9761 (5) Å	µ = 24.09 mm^−1
c = 21.841 (3) Å	T = 293 K
V = 299.03 (7) Å^3	Plate, yellow
Z = 3	0.17 × 0.11 × 0.06 mm
F(000) = 360

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	124 independent reflections
Radiation source: X-ray tube	124 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.048
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.2°, θmin = 5.6°
ω scans	h = −5→3
Absorption correction: gaussian JANA2006 (Petříček et al., 2014)	k = −4→5
Tmin = 0.111, Tmax = 0.291	l = −28→20
637 measured reflections

Refinement

Refinement on F^2	0 constraints
R[F > 3σ(F)] = 0.016	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
wR(F) = 0.040	(Δ/σ)max = 0.001
S = 1.12	Δρmax = 0.48 e Å^−3
124 reflections	Δρmin = −1.00 e Å^−3
9 parameters	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
0 restraints	Extinction coefficient: 2710 (180)

Special details

Refinement. The refinement of a model with obverse–reverse twinning turned out to be insignificant.

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0143 (8)
Tm	0.333333	0.666667	0.166667	0.0067 (3)
S	0	0	0.23376 (11)	0.0083 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0158 (10)	0.0158 (10)	0.0113 (15)	0.0079 (5)	0	0
Tm	0.0061 (4)	0.0061 (4)	0.0079 (4)	0.00307 (19)	0	0
S	0.0082 (7)	0.0082 (7)	0.0085 (11)	0.0041 (4)	0	0

Geometric parameters (Å, º)

K—S^i	3.1622 (19)	Tm—S	2.7235 (15)
K—S^ii	3.1622 (18)	Tm—S^vii	2.7234 (14)
K—S^iii	3.1622 (19)	Tm—S^viii	2.7235 (15)
K—S^iv	3.1622 (19)	Tm—S^v	2.7235 (15)
K—S^v	3.1622 (18)	Tm—S^vi	2.7235 (14)
K—S^vi	3.1622 (19)	Tm—S^ix	2.7235 (15)
S^i—K—S^ii	77.91 (4)	S—Tm—S^vi	86.23 (4)
S^i—K—S^iii	77.91 (4)	S—Tm—S^ix	180.0 (5)
S^i—K—S^iv	102.09 (4)	S^vii—Tm—S^viii	93.77 (4)
S^i—K—S^v	102.09 (4)	S^vii—Tm—S^v	86.23 (4)
S^i—K—S^vi	180.0 (5)	S^vii—Tm—S^vi	180.0 (5)
S^ii—K—S^iii	77.91 (4)	S^vii—Tm—S^ix	86.23 (4)
S^ii—K—S^iv	102.09 (4)	S^viii—Tm—S^v	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^viii—Tm—S^vi	86.23 (4)
S^ii—K—S^vi	102.09 (4)	S^viii—Tm—S^ix	86.23 (4)
S^iii—K—S^iv	180.0 (5)	S^v—Tm—S^vi	93.77 (4)
S^iii—K—S^v	102.09 (4)	S^v—Tm—S^ix	93.77 (4)
S^iii—K—S^vi	102.09 (4)	S^vi—Tm—S^ix	93.77 (4)
S^iv—K—S^v	77.91 (4)	K^x—S—K^xi	77.91 (5)
S^iv—K—S^vi	77.91 (4)	K^x—S—K^xii	77.91 (5)
S^v—K—S^vi	77.91 (4)	K^xi—S—K^xii	77.91 (5)
S—Tm—S^vii	93.77 (4)	Tm^xiii—S—Tm^xiv	93.77 (6)
S—Tm—S^viii	93.77 (4)	Tm^xiii—S—Tm	93.77 (6)
S—Tm—S^v	86.23 (4)	Tm^xiv—S—Tm	93.77 (6)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1/3, y−2/3, z+1/3; (xi) x−1/3, y+1/3, z+1/3; (xii) x+2/3, y+1/3, z+1/3; (xiii) x−1, y−1, z; (xiv) x, y−1, z.

(X) Potassium ytterbium sulfide

Crystal data

KYbS2	Dx = 4.643 Mg m^−3
Mr = 276.3	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3m	Cell parameters from 582 reflections
Hall symbol: -R 3 2"	θ = 5.6–28.9°
a = 3.9615 (8) Å	µ = 25.52 mm^−1
c = 21.810 (3) Å	T = 301 K
V = 296.42 (9) Å^3	Plate, yellow
Z = 3	0.13 × 0.11 × 0.09 mm
F(000) = 363

Data collection

Xcalibur Gemini Ultra diffractometer with Atlas detector	124 independent reflections
Radiation source: X-ray tube	124 reflections with I > 3σ(I)
Graphite monochromator	Rint = 0.069
Detector resolution: 5.1873 pixels mm^-1	θmax = 29.0°, θmin = 5.6°
ω scans	h = −2→5
Absorption correction: gaussian (JANA2006; Petříček et al., 2014)	k = −5→4
Tmin = 0.099, Tmax = 0.193	l = −29→29
444 measured reflections

Refinement

Refinement on F^2	Weighting scheme based on measured s.u.'s w = 1/[σ^2(I) + 0.0004I^2]
R[F > 3σ(F)] = 0.029	(Δ/σ)max = 0.003
wR(F) = 0.069	Δρmax = 1.42 e Å^−3
S = 1.65	Δρmin = −2.15 e Å^−3
124 reflections	Extinction correction: B-C type 1 Lorentzian isotropic [Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30, 129–147]
9 parameters	Extinction coefficient: 3900 (400)
0 restraints	Absolute structure: Refinement of a model with obverse–reverse twinning turned out to be insignificant
0 constraints

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

	x	y	z	Uiso*/Ueq
K	0	0	0	0.0133 (13)
Yb	0.333333	0.666667	0.166667	0.0063 (5)
S	0	0	0.23346 (19)	0.0072 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0146 (16)	0.0146 (16)	0.011 (2)	0.0073 (8)	0	0
Yb	0.0054 (6)	0.0054 (6)	0.0081 (7)	0.0027 (3)	0	0
S	0.0077 (12)	0.0077 (12)	0.0062 (16)	0.0039 (6)	0	0

Geometric parameters (Å, º)

K—S^i	3.159 (3)	Yb—S^ix	2.712 (2)
K—S^ii	3.159 (3)	S—S^x	3.961 (2)
K—S^iii	3.159 (3)	S—S^xi	3.9615 (16)
K—S^iv	3.159 (3)	S—S^xii	3.9615 (16)
K—S^v	3.159 (3)	S—S^vii	3.9615 (16)
K—S^vi	3.159 (3)	S—S^xiii	3.9615 (16)
Yb—S	2.712 (2)	S—S^viii	3.961 (2)
Yb—S^vii	2.712 (2)	S—S^iv	3.704 (5)
Yb—S^viii	2.712 (2)	S—S^v	3.704 (5)
Yb—S^v	2.712 (2)	S—S^vi	3.704 (5)
Yb—S^vi	2.712 (2)
S^i—K—S^ii	77.67 (6)	S—Yb—S^viii	93.85 (7)
S^i—K—S^iii	77.67 (6)	S—Yb—S^v	86.15 (7)
S^i—K—S^iv	102.33 (6)	S—Yb—S^vi	86.15 (7)
S^i—K—S^v	102.33 (6)	S—Yb—S^ix	180.0 (5)
S^i—K—S^vi	180.0 (5)	S^vii—Yb—S^viii	93.85 (7)
S^ii—K—S^iii	77.67 (6)	S^vii—Yb—S^v	86.15 (7)
S^ii—K—S^iv	102.33 (6)	S^vii—Yb—S^vi	180.0 (5)
S^ii—K—S^v	180.0 (5)	S^vii—Yb—S^ix	86.15 (7)
S^ii—K—S^vi	102.33 (6)	S^viii—Yb—S^v	180.0 (5)
S^iii—K—S^iv	180.0 (5)	S^viii—Yb—S^vi	86.15 (7)
S^iii—K—S^v	102.33 (6)	S^viii—Yb—S^ix	86.15 (7)
S^iii—K—S^vi	102.33 (6)	S^v—Yb—S^vi	93.85 (7)
S^iv—K—S^v	77.67 (6)	S^v—Yb—S^ix	93.85 (7)
S^iv—K—S^vi	77.67 (6)	S^vi—Yb—S^ix	93.85 (7)
S^v—K—S^vi	77.67 (6)	K^xiv—S—K^xv	77.67 (8)
S—Yb—S^vii	93.85 (7)	K^xiv—S—K^xvi	77.67 (9)

Symmetry codes: (i) x−2/3, y−1/3, z−1/3; (ii) x+1/3, y−1/3, z−1/3; (iii) x+1/3, y+2/3, z−1/3; (iv) y−1/3, x−2/3, −z+1/3; (v) y−1/3, x+1/3, −z+1/3; (vi) y+2/3, x+1/3, −z+1/3; (vii) x, y+1, z; (viii) x+1, y+1, z; (ix) y+2/3, x+4/3, −z+1/3; (x) x−1, y−1, z; (xi) x−1, y, z; (xii) x, y−1, z; (xiii) x+1, y, z; (xiv) x−1/3, y−2/3, z+1/3; (xv) x−1/3, y+1/3, z+1/3; (xvi) x+2/3, y+1/3, z+1/3.