Na4.25Mo15S19: a novel ternary reduced molybdenum sulfide containing Mo6 and Mo9 clusters

Salloum, D.; Gougeon, P.; Gall, P.

doi:10.1107/S160053681401201X

inorganic compounds

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Volume 70| Part 6| June 2014| Page i30

doi:10.1107/S160053681401201X

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Na_4.25Mo₁₅S₁₉: a novel ternary reduced molybdenum sulfide containing Mo₆ and Mo₉ clusters

D. Salloum,^a P. Gougeon ^b ^* and P. Gall ^b

^aFaculty of Science III, Lebanese University, PO Box 826, Kobbeh–Tripoli, Lebanon, and ^bUnité Sciences Chimiques de Rennes, UMR CNRS No. 6226, Université de Rennes I – INSA Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France
^*Correspondence e-mail: Patrick.Gougeon@univ-rennes1.fr

(Received 21 May 2014; accepted 23 May 2014; online 31 May 2014)

The structure of tetrasodium pentadecamolybdenum nonadecasulfide, Na_4.25Mo₁₅S₁₉, is isotypic with Na_3.9Mo₁₅Se₁₉ [Salloum et al. (2013 ). Acta Cryst. E69, i67–i68]. It is characterized by Mo₆Sⁱ₈S^a₆ and Mo₉Sⁱ₁₁S^a₆ (where i represents inner and a apical atoms) cluster units that are present in a 1:1 ratio. The cluster units are centered at Wyckoff positions 2b and 2c, and have point-group symmetry -3 and -6, respectively. The clusters are interconnected through additional Mo—S bonds. The Na⁺ cations occupy interunit voids formed by six or seven S atoms. One Mo, one S and one Na site [occupancy 0.751 (12)] are situated on mirror planes, and two other S atoms and one Na site (full occupancy) are situated on threefold rotation axes.

CCDC reference: 1004866

Related literature

For previous reports on the crystal structure of the In_∼3Mo₁₅Se₁₉ compounds, see: Grüttner et al. (1979 ). For physical properties of this type of compounds, see: Seeber et al. (1979 ). The crystal structures of the substituted selenides Ho_0.76In_1.68Mo₁₅Se₁₉ and In_0.87K₂Mo₁₅Se₁₉ were reported by Salloum et al. (2006 ; 2007 ). For the isotypic sulfides In_3.7Mo₁₅S₁₉, In_1.6Rb₂Mo₁₅S₁₉, In_2.2CsMo₁₅S₁₉, ScTl₂Mo₁₅S₁₉ and Na_3.9Mo₁₅Se₁₉, see: Salloum et al. (2004a ,b , 2013) and for V_1.42In_1.83Mo₁₅Se₁₉, see: Gougeon et al. (2010 ). For details of the i- and a-type ligand notation, see: Schäfer & von Schnering (1964 ).

Experimental

Crystal data

Na_4.25Mo₁₅S₁₉
M_r = 2145.95
Hexagonal, P 6₃ /m
a = 9.5340 (1) Å
c = 18.9803 (3) Å
V = 1494.11 (3) Å³
Z = 2
Mo Kα radiation
μ = 7.44 mm⁻¹
T = 293 K
0.18 × 0.14 × 0.08 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: analytical (de Meulenaar & Tompa, 1965 ) T_min = 0.363, T_max = 0.591
16576 measured reflections
1500 independent reflections
1322 reflections with I > 2σ(I)
R_int = 0.085

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.079
S = 1.13
1500 reflections
66 parameters
Δρ_max = 1.51 e Å⁻³
Δρ_min = −1.85 e Å⁻³

Data collection: COLLECT (Nonius, 1998 ); cell refinement: COLLECT; data reduction: EVALCCD (Duisenberg, 1998 ); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: DIAMOND (Bergerhoff, 1996 ); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 1004866

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681401201X/ru2060sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681401201X/ru2060Isup2.hkl

checkCIF report

Comment top

The reduced molybdenum compounds In_{3 +} _xMo₁₅X₁₉ (X = S, Se) (Grüttner et al., 1979; Salloum et al., 2004a) crystallize in an interesting structural type characterized by an equal mixture of Mo₆ and Mo₉ clusters and by In atoms that occupy two or three different crystallographically positions depending on their formal oxidation state of +1 or +3. Subsequently, isomorphous compounds such as Ho_0.76In_1.68Mo₁₅Se₁₉ (Salloum et al., 2006), In_0.87K₂Mo₁₅Se₁₉ (Salloum et al., 2007), V_1.42In_1.83Mo₁₅Se₁₉ (Gougeon et al., 2010), In_3.7Mo₁₅S₁₉ (Salloum et al., 2004a), In_1.6Rb₂Mo₁₅S₁₉, In_2.2CsMo₁₅S₁₉ and ScTl₂Mo₁₅S₁₉ (Salloum et al., 2004b) have been synthesized. In the latter compounds, the Ho, V and Sc atoms replace the trivalent indium and the K, Cs, and Tl atoms the monovalent one. Recently, we described the crystal structure of Na_3.9Mo₁₅Se₁₉ (Salloum et al., 2013) in which the sodium replaces the monovalent as well as the trivalent indium for the first time. We present here the sulfide analogue Na_4.25Mo₁₅S₁₉.

The Mo—S framework of the title compound consists of the cluster units Mo₆Sⁱ₈S^a₆ and Mo₉Sⁱ₁₁S^a₆ in a 1:1 ratio (for details of the i- and a-type ligand notation, see Schäfer & von Schnering (1964)). Both components are interconnected through additional Mo—Se bonds (Figs. 1 and 2). The first unit can be described as an Mo₆ octahedron surrounded by eight face-capping inner Sⁱ and six apical S^a ligands. The Mo₉ cluster is surrounded by 11 Sⁱ atoms capping one or two faces of the bioctahedron and six S^a ligands above the apical Mo atoms. The Mo₆Sⁱ₈S^a₆ and Mo₉Sⁱ₁₁S^a₆ units are centered at Wyckoff positions 2 b and 2c and have point-group symmetry 3 and 6, respectively. The Mo—Mo distances within the Mo₆ cluster are 2.6900 (5) Å for the distances of the Mo triangles formed by the Mo1 atoms related through the threefold axis, and 2.7098 (6) Å for the distances between these triangles. The Mo—Mo distances within the Mo₉ clusters are 2.6349 (5) and 2.6756 (7) Å in the triangles formed by the atoms Mo2 and Mo3, respectively, and 2.7081 (4) and 2.7303 (4) Å for those between the Mo2₃ and Mo3₃ triangles. All the latter Mo—Mo distances are closed to those observed in the selenide analogue indicating that the cationic charge transfer towards the Mo₆ and Mo₉ clusters are similar in both compounds. The S atoms bridge either one (S1, S2, S4 and S5) or two (S3) triangular faces of the Mo clusters. Moreover, atoms S1 and S2 are linked to an Mo atom of a neighboring cluster. The Mo—S bond distances range from 2.4184 (14) to 2.5624 (10) Å within the Mo₆Sⁱ₈S^a₆ unit, and from 2.4033 (13) to 2.5947 (8) Å within the Mo₉Sⁱ₁₁S^a₆ unit. In both cases, the shortest bonds involve the S4 and S5 terminal atoms and the longest ones correspond to the interunit Mo1—S2 and Mo2—S1 bonds. Each Mo₉Sⁱ₁₁S^a₆ cluster is thus interconnected to six Mo₆Sⁱ₈S^a₆ units (and vice versa) via Mo2—S1 bonds (and Mo1—S2 bonds, respectively), forming the three-dimensional Mo—S framework, the connective formula of which is Mo₉Sⁱ₅S^i-a_6/2S^a-i_6/2, Mo₆Sⁱ₂S^i-a_6/2S^a-i_6/2. It results from this arrangement that the shortest intercluster Mo1—Mo2 distance is 3.5202 (6) Å, indicating only weak metal-metal interactions between the Mo clusters. The Na1⁺ cations are surrounded by seven S atoms forming a distorted tricapped tetrahedron. The S5 and S2 atoms forming the tetrahedron are at 2.699 (5) and 3.1669 (13) Å from the Na1 atom, and the capping S1 atoms are at 3.3609 (19) Å. The Na2⁺ cations occupy partially at 75.1% a triangular group of distorted octahedral cavities around the threefold axis, which are formed by two Mo₆Sⁱ₈S^a₆ and three Mo₉Sⁱ₁₁S^a₆ units. The Na2—S distances are in the 2.538 (4) - 3.055 (4) Å range.

Related literature top

For previous reports on the crystal structure of the In_\sim3Mo₁₅Se₁₉ compounds, see: Grüttner et al. (1979). For physical properties of this type of compounds, see: Seeber et al. (1979). The crystal structures of the substituted selenides Ho_0.76In_1.68Mo₁₅Se₁₉ and In_0.87K₂Mo₁₅Se₁₉ were reported by Salloum et al. (2006; 2007). For the isomorphous sulfides In_3.7Mo₁₅S₁₉, In_1.6Rb₂Mo₁₅S₁₉, In_2.2CsMo₁₅S₁₉, ScTl₂Mo₁₅S₁₉ and Na_3.9Mo₁₅Se₁₉, see: Salloum et al. (2004a,b, 2013) and for V_1.42In_1.83Mo₁₅Se₁₉, see: Gougeon et al. (2010). For details of the i- and a-type ligand notation, see: Schäfer & von Schnering (1964).

Experimental top

Single crystals of Na_4.25Mo₁₅S₁₉ were prepared from an ion exchange reaction on single crystals of In_{3 +} _xMo₁₅S₁₉ with an excess of NaI at 1073 K. The mixture was sealed under vacuum in a long silica tube. The end of tube containing the crystals of In_{3 +} _xMo₁₅S₁₉ and InI was placed in a furnace with about 5 cm of the other end out from the furnace, at about the room temperature. The furnace was heated at 1073 K for 48 h. After reaction, crystals of InI were observed at the cool end of the tube. The black crystals of the title compound were subsequently washed with water to remove the excess of InI. Qualitative microanalyses using a Jeol JSM 6400 scanning electron microscope equipped with a Oxford INCA energy- dispersive-type X-ray spectrometer did not reveal the presence of indium in the crystals and indicated roughly stoichiometries comprised between 3.8 and 4.4 for the Na content.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: COLLECT (Nonius, 1998); data reduction: EVALCCD (Duisenberg, 1998); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Bergerhoff, 1996); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. : View of Na_4.25Mo₁₅S₁₉ along [110]. Displacement ellipsoids are drawn at the 97% probability level.
	Fig. 2. Plot showing the atom-numbering scheme and the interunit linkage of the Mo₉S₁₁S₆ and Mo₆S₈S₆ cluster units. Displacement ellipsoids are drawn at the 97% probability level.

Tetrasodium pentadecamolybdenum nonadecasulfide top

Crystal data top

Na_4.25Mo₁₅S₁₉	D_x = 4.770 Mg m⁻³
M_r = 2145.95	Mo Kα radiation, λ = 0.71069 Å
Hexagonal, P6₃/m	Cell parameters from 16576 reflections
a = 9.5340 (1) Å	θ = 2.2–30.0°
c = 18.9803 (3) Å	µ = 7.44 mm⁻¹
V = 1494.11 (3) Å³	T = 293 K
Z = 2	Multi-faceted crystal, black
F(000) = 1962	0.18 × 0.14 × 0.08 mm

Data collection top

Nonius KappaCCD diffractometer	1500 independent reflections
Radiation source: fine-focus sealed tube	1322 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.085
ϕ scans (κ = 0) + additional ω scans	θ_max = 30.0°, θ_min = 2.2°
Absorption correction: analytical (de Meulenaar & Tompa, 1965)	h = −12→13
T_min = 0.363, T_max = 0.591	k = −13→11
16576 measured reflections	l = −22→26

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.030	w = 1/[σ²(F_o²) + (0.0337P)² + 5.1576P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.079	(Δ/σ)_max = 0.001
S = 1.13	Δρ_max = 1.51 e Å⁻³
1500 reflections	Δρ_min = −1.85 e Å⁻³
66 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.00266 (19)

Crystal data top

Na_4.25Mo₁₅S₁₉	Z = 2
M_r = 2145.95	Mo Kα radiation
Hexagonal, P6₃/m	µ = 7.44 mm⁻¹
a = 9.5340 (1) Å	T = 293 K
c = 18.9803 (3) Å	0.18 × 0.14 × 0.08 mm
V = 1494.11 (3) Å³

Data collection top

Nonius KappaCCD diffractometer	1500 independent reflections
Absorption correction: analytical (de Meulenaar & Tompa, 1965)	1322 reflections with I > 2σ(I)
T_min = 0.363, T_max = 0.591	R_int = 0.085
16576 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	66 parameters
wR(F²) = 0.079	0 restraints
S = 1.13	Δρ_max = 1.51 e Å⁻³
1500 reflections	Δρ_min = −1.85 e Å⁻³

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Mo1	0.84424 (3)	0.01344 (3)	−0.058496 (18)	0.01072 (12)
Mo2	0.50077 (4)	−0.18303 (4)	0.131678 (19)	0.01177 (12)
Mo3	0.34797 (5)	−0.16448 (5)	0.2500	0.01301 (13)
S1	0.71650 (10)	0.02755 (11)	0.05118 (5)	0.01268 (18)
S2	0.36949 (11)	−0.01601 (11)	0.13948 (5)	0.01344 (19)
S3	0.05126 (16)	−0.30754 (17)	0.2500	0.0171 (3)
S4	0.0000	0.0000	−0.15617 (9)	0.0184 (3)
S5	0.3333	−0.3333	0.03365 (9)	0.0156 (3)
Na2	0.7703 (5)	−0.0623 (4)	−0.2500	0.0283 (12)	0.751 (12)
Na1	0.3333	−0.3333	−0.1085 (3)	0.0789 (17)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mo1	0.01252 (16)	0.01051 (16)	0.00816 (19)	0.00505 (11)	0.00061 (10)	−0.00031 (9)
Mo2	0.01434 (17)	0.01410 (17)	0.00778 (19)	0.00778 (12)	−0.00017 (10)	−0.00005 (10)
Mo3	0.0153 (2)	0.0159 (2)	0.0075 (2)	0.00754 (17)	0.000	0.000
S1	0.0121 (4)	0.0138 (4)	0.0121 (4)	0.0064 (3)	0.0013 (3)	0.0005 (3)
S2	0.0154 (4)	0.0143 (4)	0.0112 (4)	0.0079 (3)	0.0001 (3)	0.0008 (3)
S3	0.0185 (6)	0.0198 (6)	0.0133 (7)	0.0098 (5)	0.000	0.000
S4	0.0228 (5)	0.0228 (5)	0.0095 (8)	0.0114 (2)	0.000	0.000
S5	0.0187 (4)	0.0187 (4)	0.0093 (7)	0.0094 (2)	0.000	0.000
Na2	0.040 (2)	0.0256 (19)	0.026 (2)	0.0218 (16)	0.000	0.000
Na1	0.109 (3)	0.109 (3)	0.018 (2)	0.0547 (14)	0.000	0.000

Geometric parameters (Å, º) top

Mo1—S4ⁱ	2.4184 (14)	S2—Mo1^iv	2.5624 (10)
Mo1—S1	2.4492 (10)	S2—Na2^iv	2.781 (2)
Mo1—S1ⁱⁱ	2.4565 (9)	S2—Na1^iv	3.1669 (13)
Mo1—S1ⁱⁱⁱ	2.4830 (9)	S3—Mo3^viii	2.4419 (14)
Mo1—S2^iv	2.5624 (10)	S3—Na2^xi	2.538 (4)
Mo1—Mo1^v	2.6900 (5)	S3—Mo2^x	2.5947 (8)
Mo1—Mo1^vi	2.6900 (5)	S3—Mo2^viii	2.5947 (8)
Mo1—Mo1ⁱⁱⁱ	2.7098 (6)	S3—Na2^iv	3.055 (4)
Mo1—Mo1ⁱⁱ	2.7098 (6)	S4—Mo1^xii	2.4184 (14)
Mo1—Na2	3.7042 (8)	S4—Mo1^xiii	2.4184 (14)
Mo2—S5	2.4033 (13)	S4—Mo1^viii	2.4184 (14)
Mo2—S2	2.4733 (9)	S4—Na2^xiii	2.649 (3)
Mo2—S2^vii	2.5070 (9)	S4—Na2^viii	2.649 (3)
Mo2—S1	2.5429 (10)	S4—Na2^xii	2.649 (3)
Mo2—S3^vii	2.5947 (8)	S5—Mo2^viii	2.4033 (13)
Mo2—Mo2^vii	2.6349 (5)	S5—Mo2^vii	2.4033 (13)
Mo2—Mo2^viii	2.6349 (5)	S5—Na1	2.699 (5)
Mo2—Mo3^vii	2.7081 (4)	Na2—S3^xiv	2.538 (4)
Mo2—Mo3	2.7303 (4)	Na2—S4ⁱ	2.649 (3)
Mo3—S3^vii	2.4419 (14)	Na2—S4^xv	2.649 (3)
Mo3—S3	2.4504 (14)	Na2—S2^xvi	2.781 (2)
Mo3—S2^ix	2.4810 (10)	Na2—S2^iv	2.781 (2)
Mo3—S2	2.4810 (10)	Na2—Mo3^iv	2.896 (3)
Mo3—Mo3^viii	2.6756 (7)	Na2—S3^iv	3.055 (4)
Mo3—Mo3^vii	2.6756 (7)	Na2—Na2^v	3.397 (6)
Mo3—Mo2^viii	2.7081 (4)	Na2—Na2^vi	3.397 (6)
Mo3—Mo2^x	2.7081 (4)	Na2—Mo1^xvii	3.7042 (8)
Mo3—Mo2^ix	2.7303 (4)	Na1—S2^xviii	3.1669 (13)
Mo3—Na2^iv	2.896 (3)	Na1—S2^iv	3.1669 (13)
S1—Mo1ⁱⁱⁱ	2.4565 (9)	Na1—S2ⁱⁱ	3.1669 (13)
S1—Mo1ⁱⁱ	2.4830 (9)	Na1—S1^iv	3.3609 (19)
S1—Na1^iv	3.3609 (19)	Na1—S1^xviii	3.3609 (19)
S2—Mo2^viii	2.5070 (9)	Na1—S1ⁱⁱ	3.3609 (19)

S4ⁱ—Mo1—S1	171.81 (4)	Mo1—S1—Mo1ⁱⁱ	66.65 (3)
S4ⁱ—Mo1—S1ⁱⁱ	90.83 (2)	Mo1ⁱⁱⁱ—S1—Mo1ⁱⁱ	65.99 (3)
S1—Mo1—S1ⁱⁱ	89.17 (2)	Mo1—S1—Mo2	134.06 (4)
S4ⁱ—Mo1—S1ⁱⁱⁱ	90.20 (2)	Mo1ⁱⁱⁱ—S1—Mo2	130.92 (4)
S1—Mo1—S1ⁱⁱⁱ	88.56 (2)	Mo1ⁱⁱ—S1—Mo2	82.94 (3)
S1ⁱⁱ—Mo1—S1ⁱⁱⁱ	171.12 (4)	Mo1—S1—Na1^iv	127.79 (8)
S4ⁱ—Mo1—S2^iv	93.04 (4)	Mo1ⁱⁱⁱ—S1—Na1^iv	97.39 (3)
S1—Mo1—S2^iv	95.15 (3)	Mo1ⁱⁱ—S1—Na1^iv	153.45 (7)
S1ⁱⁱ—Mo1—S2^iv	91.20 (3)	Mo2—S1—Na1^iv	94.64 (6)
S1ⁱⁱⁱ—Mo1—S2^iv	97.55 (3)	Mo2—S2—Mo3	66.88 (3)
S4ⁱ—Mo1—Mo1^v	56.21 (2)	Mo2—S2—Mo2^viii	63.88 (2)
S1—Mo1—Mo1^v	116.82 (2)	Mo3—S2—Mo2^viii	65.76 (2)
S1ⁱⁱ—Mo1—Mo1^v	117.37 (2)	Mo2—S2—Mo1^iv	129.13 (4)
S1ⁱⁱⁱ—Mo1—Mo1^v	56.53 (2)	Mo3—S2—Mo1^iv	132.33 (4)
S2^iv—Mo1—Mo1^v	135.73 (2)	Mo2^viii—S2—Mo1^iv	82.07 (3)
S4ⁱ—Mo1—Mo1^vi	56.21 (2)	Mo2—S2—Na2^iv	133.09 (7)
S1—Mo1—Mo1^vi	117.46 (2)	Mo3—S2—Na2^iv	66.52 (6)
S1ⁱⁱ—Mo1—Mo1^vi	57.48 (2)	Mo2^viii—S2—Na2^iv	100.94 (8)
S1ⁱⁱⁱ—Mo1—Mo1^vi	116.43 (2)	Mo1^iv—S2—Na2^iv	87.68 (6)
S2^iv—Mo1—Mo1^vi	131.85 (2)	Mo2—S2—Na1^iv	101.03 (3)
Mo1^v—Mo1—Mo1^vi	60.0	Mo3—S2—Na1^iv	122.15 (9)
S4ⁱ—Mo1—Mo1ⁱⁱⁱ	116.37 (2)	Mo2^viii—S2—Na1^iv	160.14 (7)
S1—Mo1—Mo1ⁱⁱⁱ	56.60 (2)	Mo1^iv—S2—Na1^iv	100.15 (7)
S1ⁱⁱ—Mo1—Mo1ⁱⁱⁱ	115.84 (3)	Na2^iv—S2—Na1^iv	98.88 (10)
S1ⁱⁱⁱ—Mo1—Mo1ⁱⁱⁱ	56.08 (2)	Mo3^viii—S3—Mo3	66.31 (4)
S2^iv—Mo1—Mo1ⁱⁱⁱ	138.14 (2)	Mo3^viii—S3—Na2^xi	157.19 (11)
Mo1^v—Mo1—Mo1ⁱⁱⁱ	60.241 (8)	Mo3—S3—Na2^xi	136.50 (11)
Mo1^vi—Mo1—Mo1ⁱⁱⁱ	90.0	Mo3^viii—S3—Mo2^x	65.57 (3)
S4ⁱ—Mo1—Mo1ⁱⁱ	116.37 (2)	Mo3—S3—Mo2^x	64.86 (3)
S1—Mo1—Mo1ⁱⁱ	57.27 (2)	Na2^xi—S3—Mo2^x	119.39 (3)
S1ⁱⁱ—Mo1—Mo1ⁱⁱ	56.34 (2)	Mo3^viii—S3—Mo2^viii	65.57 (3)
S1ⁱⁱⁱ—Mo1—Mo1ⁱⁱ	115.54 (3)	Mo3—S3—Mo2^viii	64.86 (3)
S2^iv—Mo1—Mo1ⁱⁱ	134.12 (2)	Na2^xi—S3—Mo2^viii	119.39 (3)
Mo1^v—Mo1—Mo1ⁱⁱ	90.0	Mo2^x—S3—Mo2^viii	119.89 (5)
Mo1^vi—Mo1—Mo1ⁱⁱ	60.241 (8)	Mo3^viii—S3—Na2^iv	128.66 (8)
Mo1ⁱⁱⁱ—Mo1—Mo1ⁱⁱ	59.518 (16)	Mo3—S3—Na2^iv	62.35 (7)
S4ⁱ—Mo1—Na2	45.53 (6)	Na2^xi—S3—Na2^iv	74.15 (16)
S1—Mo1—Na2	142.51 (6)	Mo2^x—S3—Na2^iv	92.16 (5)
S1ⁱⁱ—Mo1—Na2	83.36 (6)	Mo2^viii—S3—Na2^iv	92.16 (5)
S1ⁱⁱⁱ—Mo1—Na2	103.55 (6)	Mo1^xii—S4—Mo1^xiii	67.58 (5)
S2^iv—Mo1—Na2	48.59 (6)	Mo1^xii—S4—Mo1^viii	67.58 (5)
Mo1^v—Mo1—Na2	99.04 (6)	Mo1^xiii—S4—Mo1^viii	67.58 (5)
Mo1^vi—Mo1—Na2	88.97 (5)	Mo1^xii—S4—Na2^xiii	151.15 (7)
Mo1ⁱⁱⁱ—Mo1—Na2	156.07 (6)	Mo1^xiii—S4—Na2^xiii	93.82 (5)
Mo1ⁱⁱ—Mo1—Na2	137.75 (5)	Mo1^viii—S4—Na2^xiii	127.12 (7)
S5—Mo2—S2	91.79 (2)	Mo1^xii—S4—Na2^viii	127.12 (7)
S5—Mo2—S2^vii	90.96 (2)	Mo1^xiii—S4—Na2^viii	151.15 (7)
S2—Mo2—S2^vii	172.09 (4)	Mo1^viii—S4—Na2^viii	93.82 (5)
S5—Mo2—S1	92.26 (3)	Na2^xiii—S4—Na2^viii	79.75 (9)
S2—Mo2—S1	89.86 (3)	Mo1^xii—S4—Na2^xii	93.82 (5)
S2^vii—Mo2—S1	97.44 (3)	Mo1^xiii—S4—Na2^xii	127.12 (7)
S5—Mo2—S3^vii	170.70 (4)	Mo1^viii—S4—Na2^xii	151.15 (7)
S2—Mo2—S3^vii	86.62 (4)	Na2^xiii—S4—Na2^xii	79.75 (9)
S2^vii—Mo2—S3^vii	89.47 (4)	Na2^viii—S4—Na2^xii	79.75 (9)
S1—Mo2—S3^vii	96.89 (3)	Mo2^viii—S5—Mo2	66.48 (4)
S5—Mo2—Mo2^vii	56.76 (2)	Mo2^viii—S5—Mo2^vii	66.48 (4)
S2—Mo2—Mo2^vii	118.56 (2)	Mo2—S5—Mo2^vii	66.48 (4)
S2^vii—Mo2—Mo2^vii	57.44 (2)	Mo2^viii—S5—Na1	140.73 (3)
S1—Mo2—Mo2^vii	136.00 (2)	Mo2—S5—Na1	140.73 (3)
S3^vii—Mo2—Mo2^vii	116.29 (3)	Mo2^vii—S5—Na1	140.73 (3)
S5—Mo2—Mo2^viii	56.76 (2)	S3^xiv—Na2—S4ⁱ	89.92 (9)
S2—Mo2—Mo2^viii	58.68 (2)	S3^xiv—Na2—S4^xv	89.92 (9)
S2^vii—Mo2—Mo2^viii	117.32 (2)	S4ⁱ—Na2—S4^xv	84.49 (12)
S1—Mo2—Mo2^viii	131.42 (2)	S3^xiv—Na2—S2^xvi	112.74 (10)
S3^vii—Mo2—Mo2^viii	115.08 (3)	S4ⁱ—Na2—S2^xvi	154.21 (15)
Mo2^vii—Mo2—Mo2^viii	60.0	S4^xv—Na2—S2^xvi	83.46 (4)
S5—Mo2—Mo3^vii	118.14 (2)	S3^xiv—Na2—S2^iv	112.74 (10)
S2—Mo2—Mo3^vii	115.63 (3)	S4ⁱ—Na2—S2^iv	83.46 (4)
S2^vii—Mo2—Mo3^vii	56.66 (2)	S4^xv—Na2—S2^iv	154.21 (15)
S1—Mo2—Mo3^vii	137.83 (3)	S2^xvi—Na2—S2^iv	97.94 (11)
S3^vii—Mo2—Mo3^vii	54.99 (3)	S3^xiv—Na2—Mo3^iv	145.61 (16)
Mo2^vii—Mo2—Mo3^vii	61.444 (11)	S4ⁱ—Na2—Mo3^iv	114.79 (9)
Mo2^viii—Mo2—Mo3^vii	90.670 (10)	S4^xv—Na2—Mo3^iv	114.79 (9)
S5—Mo2—Mo3	117.29 (2)	S2^xvi—Na2—Mo3^iv	51.78 (6)
S2—Mo2—Mo3	56.69 (2)	S2^iv—Na2—Mo3^iv	51.78 (6)
S2^vii—Mo2—Mo3	115.55 (3)	S3^xiv—Na2—S3^iv	165.85 (15)
S1—Mo2—Mo3	133.65 (3)	S4ⁱ—Na2—S3^iv	79.65 (9)
S3^vii—Mo2—Mo3	54.52 (3)	S4^xv—Na2—S3^iv	79.65 (9)
Mo2^vii—Mo2—Mo3	90.184 (10)	S2^xvi—Na2—S3^iv	75.81 (8)
Mo2^viii—Mo2—Mo3	60.600 (11)	S2^iv—Na2—S3^iv	75.81 (8)
Mo3^vii—Mo2—Mo3	58.940 (16)	Mo3^iv—Na2—S3^iv	48.54 (6)
S3^vii—Mo3—S3	173.69 (4)	S3^xiv—Na2—Na2^v	119.90 (13)
S3^vii—Mo3—S2^ix	89.88 (3)	S4ⁱ—Na2—Na2^v	50.13 (5)
S3—Mo3—S2^ix	93.48 (3)	S4^xv—Na2—Na2^v	50.13 (5)
S3^vii—Mo3—S2	89.88 (3)	S2^xvi—Na2—Na2^v	105.50 (12)
S3—Mo3—S2	93.48 (3)	S2^iv—Na2—Na2^v	105.50 (12)
S2^ix—Mo3—S2	115.45 (4)	Mo3^iv—Na2—Na2^v	94.49 (15)
S3^vii—Mo3—Mo3^viii	117.00 (4)	S3^iv—Na2—Na2^v	45.95 (11)
S3—Mo3—Mo3^viii	56.69 (4)	S3^xiv—Na2—Na2^vi	59.90 (13)
S2^ix—Mo3—Mo3^viii	118.47 (2)	S4ⁱ—Na2—Na2^vi	50.13 (5)
S2—Mo3—Mo3^viii	118.47 (2)	S4^xv—Na2—Na2^vi	50.13 (5)
S3^vii—Mo3—Mo3^vii	57.00 (4)	S2^xvi—Na2—Na2^vi	130.76 (6)
S3—Mo3—Mo3^vii	116.69 (4)	S2^iv—Na2—Na2^vi	130.76 (6)
S2^ix—Mo3—Mo3^vii	116.54 (2)	Mo3^iv—Na2—Na2^vi	154.49 (15)
S2—Mo3—Mo3^vii	116.54 (2)	S3^iv—Na2—Na2^vi	105.95 (11)
Mo3^viii—Mo3—Mo3^vii	60.0	Na2^v—Na2—Na2^vi	60.0
S3^vii—Mo3—Mo2^viii	117.827 (15)	S3^xiv—Na2—Mo1	97.96 (5)
S3—Mo3—Mo2^viii	60.149 (14)	S4ⁱ—Na2—Mo1	40.65 (3)
S2^ix—Mo3—Mo2^viii	150.01 (3)	S4^xv—Na2—Mo1	124.10 (12)
S2—Mo3—Mo2^viii	57.58 (2)	S2^xvi—Na2—Mo1	139.27 (11)
Mo3^viii—Mo3—Mo2^viii	60.944 (12)	S2^iv—Na2—Mo1	43.72 (2)
Mo3^vii—Mo3—Mo2^viii	89.804 (10)	Mo3^iv—Na2—Mo1	87.79 (5)
S3^vii—Mo3—Mo2^x	117.827 (15)	S3^iv—Na2—Mo1	80.39 (5)
S3—Mo3—Mo2^x	60.149 (14)	Na2^v—Na2—Mo1	79.33 (6)
S2^ix—Mo3—Mo2^x	57.58 (2)	Na2^vi—Na2—Mo1	87.34 (5)
S2—Mo3—Mo2^x	150.01 (3)	S3^xiv—Na2—Mo1^xvii	97.96 (5)
Mo3^viii—Mo3—Mo2^x	60.944 (12)	S4ⁱ—Na2—Mo1^xvii	124.10 (12)
Mo3^vii—Mo3—Mo2^x	89.804 (10)	S4^xv—Na2—Mo1^xvii	40.65 (3)
Mo2^viii—Mo3—Mo2^x	112.05 (2)	S2^xvi—Na2—Mo1^xvii	43.72 (2)
S3^vii—Mo3—Mo2^ix	59.911 (14)	S2^iv—Na2—Mo1^xvii	139.27 (11)
S3—Mo3—Mo2^ix	117.957 (16)	Mo3^iv—Na2—Mo1^xvii	87.79 (5)
S2^ix—Mo3—Mo2^ix	56.42 (2)	S3^iv—Na2—Mo1^xvii	80.39 (5)
S2—Mo3—Mo2^ix	146.91 (3)	Na2^v—Na2—Mo1^xvii	79.33 (6)
Mo3^viii—Mo3—Mo2^ix	89.333 (10)	Na2^vi—Na2—Mo1^xvii	87.34 (5)
Mo3^vii—Mo3—Mo2^ix	60.116 (12)	Mo1—Na2—Mo1^xvii	157.78 (11)
Mo2^viii—Mo3—Mo2^ix	146.475 (18)	S5—Na1—S2^xviii	100.69 (9)
Mo2^x—Mo3—Mo2^ix	57.956 (12)	S5—Na1—S2^iv	100.69 (9)
S3^vii—Mo3—Mo2	59.911 (14)	S2^xviii—Na1—S2^iv	116.64 (6)
S3—Mo3—Mo2	117.957 (16)	S5—Na1—S2ⁱⁱ	100.69 (9)
S2^ix—Mo3—Mo2	146.91 (3)	S2^xviii—Na1—S2ⁱⁱ	116.64 (6)
S2—Mo3—Mo2	56.42 (2)	S2^iv—Na1—S2ⁱⁱ	116.64 (6)
Mo3^viii—Mo3—Mo2	89.333 (10)	S5—Na1—S1^iv	71.10 (8)
Mo3^vii—Mo3—Mo2	60.116 (12)	S2^xviii—Na1—S1^iv	66.58 (2)
Mo2^viii—Mo3—Mo2	57.956 (12)	S2^iv—Na1—S1^iv	65.67 (2)
Mo2^x—Mo3—Mo2	146.475 (18)	S2ⁱⁱ—Na1—S1^iv	171.77 (17)
Mo2^ix—Mo3—Mo2	110.679 (19)	S5—Na1—S1^xviii	71.10 (8)
S3^vii—Mo3—Na2^iv	117.20 (8)	S2^xviii—Na1—S1^xviii	65.67 (2)
S3—Mo3—Na2^iv	69.11 (8)	S2^iv—Na1—S1^xviii	171.77 (17)
S2^ix—Mo3—Na2^iv	61.70 (3)	S2ⁱⁱ—Na1—S1^xviii	66.58 (2)
S2—Mo3—Na2^iv	61.70 (3)	S1^iv—Na1—S1^xviii	110.03 (8)
Mo3^viii—Mo3—Na2^iv	125.80 (8)	S5—Na1—S1ⁱⁱ	71.10 (8)
Mo3^vii—Mo3—Na2^iv	174.20 (8)	S2^xviii—Na1—S1ⁱⁱ	171.77 (17)
Mo2^viii—Mo3—Na2^iv	93.43 (4)	S2^iv—Na1—S1ⁱⁱ	66.58 (2)
Mo2^x—Mo3—Na2^iv	93.43 (4)	S2ⁱⁱ—Na1—S1ⁱⁱ	65.67 (2)
Mo2^ix—Mo3—Na2^iv	117.90 (3)	S1^iv—Na1—S1ⁱⁱ	110.03 (8)
Mo2—Mo3—Na2^iv	117.90 (3)	S1^xviii—Na1—S1ⁱⁱ	110.03 (8)
Mo1—S1—Mo1ⁱⁱⁱ	67.06 (3)

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

Experimental details

Crystal data
Chemical formula	Na_4.25Mo₁₅S₁₉
M_r	2145.95
Crystal system, space group	Hexagonal, P6₃/m
Temperature (K)	293
a, c (Å)	9.5340 (1), 18.9803 (3)
V (Å³)	1494.11 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	7.44
Crystal size (mm)	0.18 × 0.14 × 0.08

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Analytical (de Meulenaar & Tompa, 1965)
T_min, T_max	0.363, 0.591
No. of measured, independent and observed [I > 2σ(I)] reflections	16576, 1500, 1322
R_int	0.085
(sin θ/λ)_max (Å⁻¹)	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.079, 1.13
No. of reflections	1500
No. of parameters	66
Δρ_max, Δρ_min (e Å⁻³)	1.51, −1.85

Computer programs: COLLECT (Nonius, 1998), EVALCCD (Duisenberg, 1998), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), DIAMOND (Bergerhoff, 1996).

Acknowledgements

Intensity data were collected on the Nonius KappaCCD X-ray diffactometer system at the Centre de diffractométrie de l'Université de Rennes I (www.cdifx.univ-rennes1.fr).

References

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