Li0.5Al0.5Mg2(MoO4)3.

The title compound, lithium/aluminium dimagnesium tetra-kis-[orthomolybdate(VI)], was prepared by a solid-state reaction route. The crystal structure is built up from MgO6 octa-hedra and MoO4 tetra-hedra sharing corners and edges, forming two types of chains running along [100]. These chains are linked into layers parallel to (010) and finally linked by MoO4 tetra-hedra into a three-dimensional framework structure with channels parallel to [001] in which lithium and aluminium cations equally occupy the same position within a distorted trigonal-bipyramidal coordination environment. The title structure is isotypic with LiMgIn(MoO4)3, with the In site becoming an Mg site and the fully occupied Li site a statistically occupied Li/Al site in the title structure.

Related literature

For complex oxides containing lithium ions, see: Whittingham & Silbernagel (1976 ▶); Mizushima et al. (1980 ▶); Kanno et al. (1994 ▶). For details of chemically and/or structurally related compounds, see: Efremov & Trunov (1972 ▶); Ozima & Zoltai (1976 ▶); Klevtsov (1970 ▶); Kolitsch & Tillmanns (2003 ▶); Tsyren­ova et al. (2001 ▶, 2004 ▶); Gicquel-Mayer et al. (1981 ▶); Klevtsova & Magarill (1970 ▶); Klevtsov & Zolotova (1973 ▶); Klevtsova et al. (1979 ▶); Nord & Kierkegaard (1984 ▶); Solodov­nikov et al. (1997 ▶). For the isotypic structure of LiMgIn(MoO4)3, see: Khazheeva et al. (1985 ▶).

Experimental

Crystal data

Li0.5Al0.5Mg2(MoO4)3

M = 545.40

Triclinic,

a = 6.8555 (7) Å

b = 8.2910 (9) Å

c = 9.5760 (9) Å

α = 96.032 (7)°

β = 106.743 (8)°

γ = 101.824 (9)°

V = 502.27 (9) Å3

Z = 2

Mo Kα radiation

μ = 3.92 mm−1

T = 298 K

0.20 × 0.18 × 0.11 mm

Data collection

Enraf–Nonius CAD-4 diffractometer

Absorption correction: ψ scan (North et al., 1968 ▶) T min = 0.520, T max = 0.648

3450 measured reflections

2187 independent reflections

2150 reflections with I > 2sσ(I)

R int = 0.014

2 standard reflections every 120 min intensity decay: 1.1%

Refinement

R[F 2 > 2σ(F 2)] = 0.021

wR(F 2) = 0.053

S = 1.29

2187 reflections

164 parameters

Δρmax = 0.57 e Å−3

Δρmin = −0.81 e Å−3

Data collection: CAD-4 EXPRESS (Duisenberg, 1992 ▶; Macíček & Yordanov, 1992 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 1998 ▶); software used to prepare material for publication: WinGX (Farrugia, 2012 ▶).

Crystal structure: contains datablock(s) I. DOI: 10.1107/S1600536813022046/wm2760sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813022046/wm2760Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Li0.5Al0.5Mg2(MoO4)3	Z = 2
Mr = 545.40	F(000) = 508
Triclinic, P1	Dx = 3.606 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.8555 (7) Å	Cell parameters from 25 reflections
b = 8.2910 (9) Å	θ = 10–15°
c = 9.5760 (9) Å	µ = 3.92 mm−1
α = 96.032 (7)°	T = 298 K
β = 106.743 (8)°	Prism, colourless
γ = 101.824 (9)°	0.2 × 0.18 × 0.11 mm
V = 502.27 (9) Å3

Enraf–Nonius CAD-4 diffractometer	2150 reflections with I > 2sσ(I)
Radiation source: fine-focus sealed tube	Rint = 0.014
Graphite monochromator	θmax = 27.0°, θmin = 2.3°
ω/2θ scans	h = −8→4
Absorption correction: ψ scan (North et al., 1968)	k = −10→10
Tmin = 0.520, Tmax = 0.648	l = −12→12
3450 measured reflections	2 standard reflections every 120 min
2187 independent reflections	intensity decay: 1.1%

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)] = 0.021	w = 1/[σ2(Fo2) + (0.0096P)2 + 2.5823P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.053	(Δ/σ)max = 0.001
S = 1.29	Δρmax = 0.57 e Å−3
2187 reflections	Δρmin = −0.81 e Å−3
164 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraints	Extinction coefficient: 0.0123 (4)

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
Mo1	0.30272 (5)	0.89586 (4)	0.66046 (3)	0.00921 (10)
Mo2	0.98153 (5)	0.19503 (4)	0.87863 (4)	0.01148 (10)
Mo3	0.49457 (5)	0.50622 (4)	0.74760 (3)	0.00964 (10)
Mg1	0.53871 (19)	0.19031 (15)	0.99366 (13)	0.0071 (2)
Mg2	0.2478 (2)	0.20149 (16)	0.40750 (14)	0.0096 (2)
Li1	0.0379 (4)	0.6097 (3)	0.7889 (3)	0.0200 (5)	0.50
Al1	0.0379 (4)	0.6097 (3)	0.7889 (3)	0.0200 (5)	0.50
O1	0.0505 (4)	0.7660 (3)	0.6386 (3)	0.0131 (5)
O2	0.4454 (4)	0.9765 (4)	0.8546 (3)	0.0147 (6)
O3	0.9874 (5)	0.3666 (4)	0.7886 (4)	0.0252 (7)
O4	0.5435 (5)	0.3564 (4)	0.8579 (3)	0.0212 (6)
O5	0.2586 (5)	0.0618 (4)	0.5726 (3)	0.0197 (6)
O6	0.8558 (5)	0.0118 (4)	0.7493 (3)	0.0212 (6)
O7	0.7368 (4)	0.6232 (4)	0.7376 (3)	0.0138 (5)
O8	0.3563 (4)	0.6386 (4)	0.8234 (3)	0.0151 (6)
O9	0.3363 (5)	0.4040 (4)	0.5737 (3)	0.0165 (6)
O10	0.8481 (5)	0.2198 (4)	0.0140 (3)	0.0180 (6)
O11	0.2432 (5)	0.1911 (4)	0.9700 (4)	0.0226 (7)
O12	0.4468 (5)	0.7896 (4)	0.5776 (3)	0.0177 (6)

	U11	U22	U33	U12	U13	U23
Mo1	0.00817 (16)	0.01051 (16)	0.00822 (16)	0.00090 (12)	0.00288 (12)	0.00056 (11)
Mo2	0.01273 (17)	0.01071 (17)	0.01133 (17)	0.00244 (12)	0.00502 (12)	0.00086 (12)
Mo3	0.00894 (16)	0.01052 (16)	0.00917 (16)	0.00232 (12)	0.00293 (12)	0.00046 (11)
Mg1	0.0077 (6)	0.0069 (6)	0.0065 (5)	0.0020 (4)	0.0020 (4)	0.0006 (4)
Mg2	0.0088 (6)	0.0097 (6)	0.0094 (6)	0.0014 (5)	0.0027 (5)	0.0008 (5)
Li1	0.0172 (10)	0.0215 (11)	0.0203 (11)	0.0038 (9)	0.0046 (9)	0.0060 (9)
Al1	0.0172 (10)	0.0215 (11)	0.0203 (11)	0.0038 (9)	0.0046 (9)	0.0060 (9)
O1	0.0111 (13)	0.0137 (13)	0.0147 (13)	0.0028 (10)	0.0041 (11)	0.0044 (11)
O2	0.0121 (13)	0.0172 (14)	0.0128 (13)	0.0036 (11)	0.0025 (11)	−0.0018 (11)
O3	0.0305 (18)	0.0179 (15)	0.0298 (17)	0.0038 (13)	0.0127 (15)	0.0103 (13)
O4	0.0207 (15)	0.0250 (16)	0.0204 (15)	0.0089 (13)	0.0064 (13)	0.0084 (13)
O5	0.0244 (16)	0.0160 (14)	0.0180 (15)	0.0025 (12)	0.0064 (12)	0.0054 (12)
O6	0.0240 (16)	0.0198 (15)	0.0170 (15)	0.0020 (13)	0.0071 (13)	−0.0033 (12)
O7	0.0124 (13)	0.0158 (13)	0.0140 (13)	0.0050 (11)	0.0047 (11)	0.0024 (11)
O8	0.0136 (13)	0.0153 (14)	0.0175 (14)	0.0030 (11)	0.0081 (11)	−0.0004 (11)
O9	0.0187 (14)	0.0140 (14)	0.0126 (13)	0.0001 (11)	0.0028 (11)	−0.0011 (11)
O10	0.0222 (15)	0.0206 (15)	0.0150 (14)	0.0092 (12)	0.0084 (12)	0.0040 (12)
O11	0.0200 (15)	0.0275 (17)	0.0219 (16)	0.0080 (13)	0.0079 (13)	0.0031 (13)
O12	0.0147 (14)	0.0219 (15)	0.0157 (14)	0.0038 (12)	0.0056 (11)	−0.0016 (12)

Mo1—O5i	1.721 (3)	Mg1—O4	1.992 (3)
Mo1—O12	1.745 (3)	Mg1—O10iii	2.033 (3)
Mo1—O1	1.781 (3)	Mg1—O2v	2.104 (3)
Mo1—O2	1.812 (3)	Mg2—O12vi	2.042 (3)
Mo2—O3	1.738 (3)	Mg2—O1vii	2.045 (3)
Mo2—O6	1.743 (3)	Mg2—O9	2.046 (3)
Mo2—O11ii	1.763 (3)	Mg2—O5	2.049 (3)
Mo2—O10iii	1.807 (3)	Mg2—O6viii	2.049 (3)
Mo3—O9	1.718 (3)	Mg2—O7vi	2.121 (3)
Mo3—O4	1.736 (3)	Li1—O3ix	1.974 (4)
Mo3—O7	1.777 (3)	Li1—O7ix	2.009 (4)
Mo3—O8	1.812 (3)	Li1—O1	2.044 (4)
Mg1—O2iv	1.968 (3)	Li1—O8	2.070 (4)
Mg1—O11	1.974 (3)	Li1—O10vi	2.076 (4)
Mg1—O8v	1.983 (3)
O5i—Mo1—O12	108.83 (15)	O11—Mg1—O2v	94.31 (13)
O5i—Mo1—O1	106.36 (14)	O8v—Mg1—O2v	82.89 (12)
O12—Mo1—O1	111.36 (14)	O4—Mg1—O2v	176.13 (14)
O5i—Mo1—O2	108.44 (14)	O10iii—Mg1—O2v	91.76 (12)
O12—Mo1—O2	111.03 (13)	O12vi—Mg2—O1vii	166.46 (14)
O1—Mo1—O2	110.64 (13)	O12vi—Mg2—O9	91.79 (13)
O3—Mo2—O6	109.58 (16)	O1vii—Mg2—O9	86.88 (13)
O3—Mo2—O11ii	108.05 (16)	O12vi—Mg2—O5	92.20 (14)
O6—Mo2—O11ii	109.67 (15)	O1vii—Mg2—O5	101.11 (13)
O3—Mo2—O10iii	108.85 (15)	O9—Mg2—O5	85.35 (13)
O6—Mo2—O10iii	111.40 (15)	O12vi—Mg2—O6viii	91.25 (13)
O11ii—Mo2—O10iii	109.23 (14)	O1vii—Mg2—O6viii	91.06 (13)
O9—Mo3—O4	107.98 (15)	O9—Mg2—O6viii	175.12 (14)
O9—Mo3—O7	109.75 (14)	O5—Mg2—O6viii	90.72 (14)
O4—Mo3—O7	109.09 (14)	O12vi—Mg2—O7vi	85.67 (13)
O9—Mo3—O8	108.76 (14)	O1vii—Mg2—O7vi	80.80 (12)
O4—Mo3—O8	109.30 (14)	O9—Mg2—O7vi	86.40 (12)
O7—Mo3—O8	111.88 (13)	O5—Mg2—O7vi	171.41 (13)
O2iv—Mg1—O11	90.13 (14)	O6viii—Mg2—O7vi	97.64 (13)
O2iv—Mg1—O8v	163.23 (14)	O3ix—Li1—O7ix	97.36 (16)
O11—Mg1—O8v	92.29 (13)	O3ix—Li1—O1	137.17 (18)
O2iv—Mg1—O4	102.01 (14)	O7ix—Li1—O1	83.58 (14)
O11—Mg1—O4	88.75 (14)	O3ix—Li1—O8	93.03 (16)
O8v—Mg1—O4	94.64 (14)	O7ix—Li1—O8	168.56 (17)
O2iv—Mg1—O10iii	94.68 (13)	O1—Li1—O8	85.55 (14)
O11—Mg1—O10iii	172.82 (15)	O3ix—Li1—O10vi	121.05 (17)
O8v—Mg1—O10iii	84.64 (13)	O7ix—Li1—O10vi	97.16 (15)
O4—Mg1—O10iii	85.04 (13)	O1—Li1—O10vi	101.10 (15)
O2iv—Mg1—O2v	80.38 (13)	O8—Li1—O10vi	81.44 (14)

Table 1

Selected bond lengths (Å)

Mo1—O5i	1.721 (3)
Mo1—O12	1.745 (3)
Mo1—O1	1.781 (3)
Mo1—O2	1.812 (3)
Mo2—O3	1.738 (3)
Mo2—O6	1.743 (3)
Mo2—O11ii	1.763 (3)
Mo2—O10iii	1.807 (3)
Mo3—O9	1.718 (3)
Mo3—O4	1.736 (3)
Mo3—O7	1.777 (3)
Mo3—O8	1.812 (3)
Mg1—O2iv	1.968 (3)
Mg1—O11	1.974 (3)
Mg1—O8v	1.983 (3)
Mg1—O4	1.992 (3)
Mg1—O10iii	2.033 (3)
Mg1—O2v	2.104 (3)
Mg2—O12vi	2.042 (3)
Mg2—O1vii	2.045 (3)
Mg2—O9	2.046 (3)
Mg2—O5	2.049 (3)
Mg2—O6viii	2.049 (3)
Mg2—O7vi	2.121 (3)
Li1—O3ix	1.974 (4)
Li1—O7ix	2.009 (4)
Li1—O1	2.044 (4)
Li1—O8	2.070 (4)
Li1—O10vi	2.076 (4)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) ; (vi) ; (vii) ; (viii) ; (ix) .