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The title compound, sodium tetramagnesium tris­(arsenate), was prepared by solid-state reaction at 1243 K. The structure is built up from edge-sharing MgO6 octahedra associated with the AsO4 arsenate groups. The three-dimensional network encloses cavities in which Na+ cations are located. This compound exhibits the NaMg4(VO4)3 structure. The Na and one of the As atoms are on positions of \overline 4 symmetry and the remaining cations all lie on twofold axes.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536804012772/br6150sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536804012772/br6150Isup2.hkl
Contains datablock I

Key indicators

  • Single-crystal X-ray study
  • T = 293 K
  • Mean [sigma](Mg-O) = 0.003 Å
  • R factor = 0.018
  • wR factor = 0.045
  • Data-to-parameter ratio = 10.9

checkCIF/PLATON results

No syntax errors found



Alert level A PLAT052_ALERT_1_A (Proper) Absorption Correction Method Missing .. ? PLAT057_ALERT_3_A Correction for Absorption Required RT(exp) ... 1.60
Alert level G REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is correct. If it is not, please give the correct count in the _publ_section_exptl_refinement section of the submitted CIF. From the CIF: _diffrn_reflns_theta_max 27.93 From the CIF: _reflns_number_total 525 Count of symmetry unique reflns 322 Completeness (_total/calc) 163.04% TEST3: Check Friedels for noncentro structure Estimate of Friedel pairs measured 203 Fraction of Friedel pairs measured 0.630 Are heavy atom types Z>Si present yes
2 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 0 ALERT level C = Check and explain 1 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion

Computing details top

Data collection: CAD-4 EXPRESS (Duisenberg, 1992; Macíček & Yordanov, 1992); cell refinement: CAD-4 EXPRESS; data reduction: MolEN (Fair, 1990); program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97.

Sodium tetramagnesium tris(arsenate) top
Crystal data top
NaMg4(AsO4)3Dx = 3.989 Mg m3
Mr = 536.96Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I42dCell parameters from 25 reflections
Hall symbol: I -4 2bwθ = 2–27°
a = 6.817 (1) ŵ = 11.55 mm1
c = 19.242 (3) ÅT = 293 K
V = 894.2 (2) Å3Prismatic, colourless
Z = 40.1 × 0.07 × 0.04 mm
F(000) = 1016
Data collection top
Enraf-Nonius CAD-4
diffractometer
500 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 27.9°, θmin = 3.2°
ω/2θ scansh = 84
Absorption correction: ψ scan
(North et al., 1968)
k = 18
Tmin = 0.394, Tmax = 0.630l = 125
1111 measured reflections2 standard reflections every 120 min
525 independent reflections intensity decay: 0.4%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: full w = 1/[σ2(Fo2) + (0.0194P)2]
where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.018(Δ/σ)max < 0.001
wR(F2) = 0.045Δρmax = 0.39 e Å3
S = 1.10Δρmin = 0.49 e Å3
525 reflectionsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
48 parametersExtinction coefficient: 0.0016 (3)
0 restraintsAbsolute structure: Flack (1983), with xx Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.003 (17)
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
xyzUiso*/Ueq
As10.00000.00000.00000.00350 (18)
As20.34467 (8)0.75000.12500.00424 (15)
Mg10.00000.50000.02054 (9)0.0061 (4)
Mg20.7588 (3)0.75000.12500.0064 (4)
Na0.50000.50000.00000.0128 (7)
O10.5064 (4)0.7959 (4)0.05961 (13)0.0077 (6)
O20.2227 (4)0.5460 (4)0.09958 (12)0.0070 (5)
O30.0581 (4)0.2068 (4)0.04410 (13)0.0073 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
As10.0037 (2)0.0037 (2)0.0032 (3)0.0000.0000.000
As20.0048 (3)0.0038 (3)0.0041 (2)0.0000.0000.0000 (2)
Mg10.0090 (9)0.0052 (9)0.0041 (7)0.0000 (8)0.0000.000
Mg20.0059 (8)0.0076 (8)0.0056 (9)0.0000.0000.0014 (7)
Na0.0121 (10)0.0121 (10)0.0141 (15)0.0000.0000.000
O10.0078 (11)0.0104 (14)0.0050 (10)0.0004 (10)0.0000 (10)0.0023 (10)
O20.0096 (13)0.0026 (12)0.0089 (11)0.0013 (11)0.0022 (11)0.0000 (9)
O30.0101 (12)0.0048 (14)0.0072 (12)0.0006 (10)0.0016 (10)0.0038 (10)
Geometric parameters (Å, º) top
As1—O3i1.692 (3)Mg2—O3ix2.017 (3)
As1—O3ii1.692 (3)Mg2—O3x2.017 (3)
As1—O31.692 (3)Mg2—O2xi2.080 (3)
As1—O3iii1.692 (3)Mg2—O2xii2.080 (3)
As2—O2iv1.693 (2)Mg2—O12.154 (3)
As2—O21.693 (2)Mg2—O1iv2.154 (3)
As2—O1iv1.702 (3)Na—O1vi2.321 (3)
As2—O11.702 (3)Na—O1xi2.321 (3)
Mg1—O1v2.078 (3)Na—O1xiii2.321 (3)
Mg1—O1vi2.078 (3)Na—O12.321 (3)
Mg1—O3iii2.088 (3)Na—O2xi2.710 (3)
Mg1—O3vii2.088 (3)Na—O22.710 (3)
Mg1—O22.171 (3)Na—O2xiii2.710 (3)
Mg1—O2viii2.171 (3)Na—O2vi2.710 (3)
O3i—As1—O3ii119.81 (18)O2xi—Mg2—O192.98 (11)
O3i—As1—O3104.56 (8)O2xii—Mg2—O192.57 (11)
O3ii—As1—O3104.56 (8)O3ix—Mg2—O1iv91.27 (10)
O3i—As1—O3iii104.56 (8)O3x—Mg2—O1iv165.05 (12)
O3ii—As1—O3iii104.56 (8)O2xi—Mg2—O1iv92.57 (11)
O3—As1—O3iii119.81 (18)O2xii—Mg2—O1iv92.98 (11)
O2iv—As2—O2121.14 (19)O1—Mg2—O1iv74.00 (15)
O2iv—As2—O1iv104.82 (13)O1vi—Na—O1xi104.14 (6)
O2—As2—O1iv112.38 (13)O1vi—Na—O1xiii120.77 (12)
O2iv—As2—O1112.38 (13)O1xi—Na—O1xiii104.14 (6)
O2—As2—O1104.82 (13)O1vi—Na—O1104.14 (6)
O1iv—As2—O199.24 (18)O1xi—Na—O1120.77 (12)
O1v—Mg1—O1vi84.13 (16)O1xiii—Na—O1104.14 (6)
O1v—Mg1—O3iii105.55 (11)O1vi—Na—O2xi163.33 (8)
O1vi—Mg1—O3iii93.11 (10)O1xi—Na—O2xi64.10 (8)
O1v—Mg1—O3vii93.11 (10)O1xiii—Na—O2xi74.98 (8)
O1vi—Mg1—O3vii105.55 (11)O1—Na—O2xi74.81 (8)
O3iii—Mg1—O3vii154.92 (16)O1vi—Na—O274.98 (8)
O1v—Mg1—O2172.35 (11)O1xi—Na—O274.81 (8)
O1vi—Mg1—O292.80 (10)O1xiii—Na—O2163.33 (8)
O3iii—Mg1—O281.57 (10)O1—Na—O264.10 (8)
O3vii—Mg1—O280.93 (11)O2xi—Na—O290.01 (11)
O1v—Mg1—O2viii92.80 (10)O1vi—Na—O2xiii74.81 (8)
O1vi—Mg1—O2viii172.35 (11)O1xi—Na—O2xiii163.33 (8)
O3iii—Mg1—O2viii80.93 (11)O1xiii—Na—O2xiii64.10 (8)
O3vii—Mg1—O2viii81.57 (10)O1—Na—O2xiii74.98 (8)
O2—Mg1—O2viii91.08 (15)O2xi—Na—O2xiii120.00 (6)
O3ix—Mg2—O3x103.55 (17)O2—Na—O2xiii120.00 (6)
O3ix—Mg2—O2xi90.13 (11)O1vi—Na—O2vi64.10 (8)
O3x—Mg2—O2xi85.57 (11)O1xi—Na—O2vi74.98 (8)
O3ix—Mg2—O2xii85.57 (11)O1xiii—Na—O2vi74.81 (8)
O3x—Mg2—O2xii90.13 (11)O1—Na—O2vi163.33 (8)
O2xi—Mg2—O2xii173.04 (19)O2xi—Na—O2vi120.00 (6)
O3ix—Mg2—O1165.05 (12)O2—Na—O2vi120.00 (6)
O3x—Mg2—O191.27 (10)O2xiii—Na—O2vi90.01 (11)
Symmetry codes: (i) y, x, z; (ii) y, x, z; (iii) x, y, z; (iv) x, y3/2, z+1/4; (v) y1, x1, z; (vi) y+1, x, z; (vii) x, y1, z; (viii) x, y1, z; (ix) x+1, y1/2, z+1/4; (x) x+1, y1, z; (xi) x+1, y1, z; (xii) x+1, y1/2, z+1/4; (xiii) y, x1, z.
 

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