Reinvestigation of MnSn₂

The structure of manganese distannite, MnSn₂, known from X-ray powder diffraction data, has been refined based on single-crystal data. This inter­metallic compound crystallizes in the tetra­gonal CuAl₂ structure type. Mn atoms (4a position) form chains parallel to the c axis and each Mn atom is surrounded by eight Sn atoms in a square anti­prism. Each Sn atom (8h position) has four Mn near neighbors from two neighboring Mn chains forming Mn₄Sn recta­ngular prisms.

Key indicators

• Single-crystal X-ray study
• T = 157 K
• Mean [sigma]() = 0.000 Å
• R factor = 0.016
• wR factor = 0.030
• Data-to-parameter ratio = 26.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.95
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(13) ......       2.31 su-Rat
              MN   -SN      1.555  25.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(13) ......       2.31 su-Rat
              MN   -SN      1.555  17.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(14) ......       2.14 su-Rat
              MN   -SN      1.555   9.445
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(13) ......       2.31 su-Rat
              MN   -SN      1.555  11.545
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(14) ......       2.14 su-Rat
              MN   -SN      1.555  27.455
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(14) ......       2.14 su-Rat
              MN   -SN      1.555   1.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(14) ......       2.14 su-Rat
              MN   -SN      1.555  19.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(13) ......       2.31 su-Rat
              MN   -SN      1.555   3.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(14) ......       2.14 su-Rat
              SN   -MN      1.555  25.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(13) ......       2.31 su-Rat
              SN   -MN      1.555  17.555
PLAT731_ALERT_1_C Bond    Calc   2.8366(3), Rep 2.83663(14) ......       2.14 su-Rat
              SN   -MN      1.555   9.554

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
  12 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

  11 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
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: APEX2 (Bruker, 2003); cell refinement: APEX2; data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 1999).

manganese distannite

Crystal data

MnSn2	Dx = 8.115 Mg m^−3
Mr = 292.32	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4/mcm	Cell parameters from 907 reflections
Hall symbol: -I 4 2c	θ = 6.1–39.3°
a = 6.6438 (3) Å	µ = 25.48 mm^−1
c = 5.4206 (6) Å	T = 157 K
V = 239.27 (3) Å^3	Needle, black
Z = 4	0.08 × 0.02 × 0.02 mm
F(000) = 500

Data collection

Bruker X8 APEX II 4K CCD area-detector diffractometer	209 independent reflections
Radiation source: fine-focus sealed tube	199 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.034
φ and ω scans	θmax = 39.3°, θmin = 4.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −10→7
Tmin = 0.346, Tmax = 0.630	k = −11→11
1402 measured reflections	l = −9→9

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) + (0.0047P)^2 + 0.2469P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.030	(Δ/σ)max < 0.001
S = 1.22	Δρmax = 1.21 e Å^−3
209 reflections	Δρmin = −1.44 e Å^−3
8 parameters	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0143 (8)

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
Mn	0.0000	0.0000	0.2500	0.00487 (12)
Sn	0.33857 (2)	0.16143 (2)	0.0000	0.00554 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn	0.00495 (17)	0.00495 (17)	0.0047 (2)	0.000	0.000	0.000
Sn	0.00523 (10)	0.00523 (10)	0.00617 (11)	−0.00057 (6)	0.000	0.000

Geometric parameters (Å, º)

Mn—Mn^i	2.7103 (3)	Mn—Sn^vii	2.8366 (1)
Mn—Mn^ii	2.7103 (3)	Mn—Sn^viii	2.8366 (1)
Mn—Sn^iii	2.8366 (1)	Sn—Mn^iii	2.8366 (1)
Mn—Sn^ii	2.8366 (1)	Sn—Mn^ii	2.8366 (1)
Mn—Sn^iv	2.8366 (1)	Sn—Mn^ix	2.8366 (1)
Mn—Sn^v	2.8366 (1)	Sn—Sn^x	3.0335 (4)
Mn—Sn^vi	2.8366 (1)	Sn—Sn^iii	3.1805 (3)
Mn—Sn	2.8366 (1)	Sn—Sn^xi	3.1805 (3)
Mn^i—Mn—Mn^ii	180.0	Sn^v—Mn—Sn^vii	68.197 (6)
Mn^i—Mn—Sn^iii	61.463 (3)	Sn^vi—Mn—Sn^vii	145.880 (7)
Mn^ii—Mn—Sn^iii	118.537 (3)	Sn—Mn—Sn^vii	76.807 (3)
Mn^i—Mn—Sn^ii	118.537 (3)	Mn^i—Mn—Sn^viii	118.537 (3)
Mn^ii—Mn—Sn^ii	61.463 (3)	Mn^ii—Mn—Sn^viii	61.463 (3)
Sn^iii—Mn—Sn^ii	145.880 (7)	Sn^iii—Mn—Sn^viii	75.070 (7)
Mn^i—Mn—Sn^iv	61.463 (3)	Sn^ii—Mn—Sn^viii	76.807 (3)
Mn^ii—Mn—Sn^iv	118.537 (3)	Sn^iv—Mn—Sn^viii	135.569 (7)
Sn^iii—Mn—Sn^iv	122.925 (6)	Sn^v—Mn—Sn^viii	145.880 (7)
Sn^ii—Mn—Sn^iv	68.197 (6)	Sn^vi—Mn—Sn^viii	68.197 (6)
Mn^i—Mn—Sn^v	61.463 (3)	Sn—Mn—Sn^viii	76.807 (2)
Mn^ii—Mn—Sn^v	118.537 (3)	Sn^vii—Mn—Sn^viii	122.925 (6)
Sn^iii—Mn—Sn^v	76.807 (3)	Mn^iii—Sn—Mn^ii	145.880 (7)
Sn^ii—Mn—Sn^v	135.569 (7)	Mn^iii—Sn—Mn	111.803 (6)
Sn^iv—Mn—Sn^v	76.807 (3)	Mn^ii—Sn—Mn	57.075 (6)
Mn^i—Mn—Sn^vi	61.463 (3)	Mn^iii—Sn—Mn^ix	57.075 (6)
Mn^ii—Mn—Sn^vi	118.537 (3)	Mn^ii—Sn—Mn^ix	111.803 (6)
Sn^iii—Mn—Sn^vi	76.807 (3)	Mn—Sn—Mn^ix	145.880 (7)
Sn^ii—Mn—Sn^vi	75.070 (7)	Mn^iii—Sn—Sn^x	107.060 (4)
Sn^iv—Mn—Sn^vi	76.807 (3)	Mn^ii—Sn—Sn^x	107.060 (4)
Sn^v—Mn—Sn^vi	122.925 (6)	Mn—Sn—Sn^x	107.060 (4)
Mn^i—Mn—Sn	118.537 (3)	Mn^ix—Sn—Sn^x	107.060 (4)
Mn^ii—Mn—Sn	61.463 (3)	Mn^iii—Sn—Sn^iii	55.901 (3)
Sn^iii—Mn—Sn	68.197 (6)	Mn^ii—Sn—Sn^iii	104.689 (7)
Sn^ii—Mn—Sn	122.925 (6)	Mn—Sn—Sn^iii	55.901 (3)
Sn^iv—Mn—Sn	145.880 (7)	Mn^ix—Sn—Sn^iii	104.689 (7)
Sn^v—Mn—Sn	75.070 (7)	Sn^x—Sn—Sn^iii	121.554 (7)
Sn^vi—Mn—Sn	135.569 (7)	Mn^iii—Sn—Sn^xi	104.689 (7)
Mn^i—Mn—Sn^vii	118.537 (3)	Mn^ii—Sn—Sn^xi	55.901 (3)
Mn^ii—Mn—Sn^vii	61.463 (3)	Mn—Sn—Sn^xi	104.689 (7)
Sn^iii—Mn—Sn^vii	135.569 (7)	Mn^ix—Sn—Sn^xi	55.901 (3)
Sn^ii—Mn—Sn^vii	76.807 (3)	Sn^x—Sn—Sn^xi	121.554 (7)
Sn^iv—Mn—Sn^vii	75.070 (7)	Sn^iii—Sn—Sn^xi	116.893 (13)

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