Tetrapotassium dodeca-μ-chloro-hexa­chloro-octahedro-hexatantalate, K₄[Ta₆Cl₁₂]Cl₆

K₄[Ta₆Cl₁₂]Cl₆ was obtained as a by-product during the reaction of VCl₃ and KCl in a sealed tantalum container. The compound is isotypic to K₄Nb₆Cl₁₈ [Simon, von Schnering & Schäfer (1968). Z. Anorg. Allg. Chem. 361, 235–246] and contains octahedral ([Ta₆Cl₁₂]Cl₆)⁴⁻ clusters with 2/m site symmetry.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](Ta-Cl) = 0.002 Å
• R factor = 0.029
• wR factor = 0.067
• Data-to-parameter ratio = 23.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?

Alert level G
ABSTM02_ALERT_3_G  The ratio of expected to reported Tmax/Tmin(RR) is > 1.50
            Tmin and Tmax reported:      0.034     0.101
            Tmin and Tmax expected:      0.017     0.079
            RR =      1.603
            Please check that your absorption correction is appropriate.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 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
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1996).

(I)

Crystal data

K4[Ta6Cl12]Cl6	F(000) = 1640
Mr = 1880.20	Dx = 4.406 Mg m^−3
Monoclinic, C2/m	Melting point: unknown K
Hall symbol: -C 2y	Mo Kα radiation, λ = 0.71073 Å
a = 9.9900 (12) Å	Cell parameters from 18943 reflections
b = 16.5228 (18) Å	θ = 0–42.7°
c = 9.4745 (10) Å	µ = 25.34 mm^−1
β = 115.005 (8)°	T = 293 K
V = 1417.3 (3) Å^3	Polyhedron, black
Z = 2	0.2 × 0.2 × 0.1 mm

Data collection

Stoe IPDS-II diffractometer	1608 independent reflections
Radiation source: fine-focus sealed tube	1423 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.066
Detector resolution: not measured pixels mm^-1	θmax = 27.0°, θmin = 2.4°
ω and φ scans	h = −12→12
Absorption correction: numerical [X-RED (Stoe & Cie, 2002) and X-SHAPE (Stoe & Cie, 1999)]	k = −21→21
Tmin = 0.034, Tmax = 0.101	l = −12→12
9391 measured reflections

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)] = 0.029	w = 1/[σ^2(Fo^2) + (0.04P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.067	(Δ/σ)max < 0.001
S = 1.04	Δρmax = 1.75 e Å^−3
1608 reflections	Δρmin = −1.75 e Å^−3
70 parameters	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.00046 (6)

Special details

Experimental. A suitable single-crystal was carefully selected under a polarizing microscope and mounted in a glass capillary. The scattering intensities were collected with an imaging plate diffractometer (Stoe IPDS-I) equipped with a fine focus sealed tube X-ray source (Mo Kα, λ = 0.71073 Å) operating at 50 kV and 40 mA. Intensity data for K₄[Ta₆Cl₁₂]Cl₆ were collected at 293 K by ω scans in 302 frames (0 < ω < 180°; 0 < φ < 0°, 0 < ω < 151°; φ = 90°, Δω = 1°, exposure time of 5 min) in the 2Θ range 5.46–54.00°. Structure solution and refinement were carried out using the program SHELXL97 (Sheldrick, 1997). A numerical absorption correction (X-RED (Stoe & Cie, 2001) was applied after optimization of the crystal shape (X-SHAPE (Stoe & Cie, 1999)). The final difference maps were free of any chemically significant features. The refinement was based on F² for ALL reflections.

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
Ta1	0.13562 (3)	0.087457 (18)	0.64130 (3)	0.02921 (12)
Ta2	0.11908 (4)	0.0000	0.36889 (5)	0.02920 (13)
Cl1	0.3027 (2)	0.10501 (14)	0.5121 (2)	0.0408 (4)
Cl2	−0.0201 (2)	−0.10454 (13)	0.1776 (2)	0.0384 (4)
Cl3	0.0000	0.20882 (17)	0.5000	0.0402 (6)
Cl4	0.3258 (3)	0.0000	0.8353 (3)	0.0371 (6)
Cl5	0.3076 (2)	0.19833 (14)	0.8224 (2)	0.0446 (5)
Cl6	0.2689 (3)	0.0000	0.2073 (4)	0.0469 (7)
K	0.3909 (2)	0.16121 (16)	0.1773 (3)	0.0593 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ta1	0.02324 (17)	0.03582 (19)	0.02503 (17)	−0.00184 (10)	0.00676 (11)	−0.00148 (10)
Ta2	0.0226 (2)	0.0385 (2)	0.0252 (2)	0.000	0.00883 (15)	0.000
Cl1	0.0320 (9)	0.0549 (12)	0.0360 (9)	−0.0125 (8)	0.0149 (8)	−0.0055 (8)
Cl2	0.0349 (9)	0.0496 (11)	0.0307 (8)	−0.0027 (8)	0.0140 (7)	−0.0067 (8)
Cl3	0.0404 (14)	0.0366 (13)	0.0346 (13)	0.000	0.0072 (11)	0.000
Cl4	0.0267 (11)	0.0460 (15)	0.0292 (12)	0.000	0.0027 (9)	0.000
Cl5	0.0361 (10)	0.0494 (12)	0.0412 (11)	−0.0067 (8)	0.0093 (8)	−0.0092 (8)
Cl6	0.0422 (14)	0.0603 (19)	0.0459 (16)	0.000	0.0261 (13)	0.000
K	0.0507 (11)	0.0672 (14)	0.0605 (13)	0.0080 (10)	0.0239 (10)	0.0133 (11)

Geometric parameters (Å, º)

Ta1—Cl2^i	2.455 (2)	Cl1—K	3.750 (3)
Ta1—Cl1	2.469 (2)	Cl2—Ta1^i	2.455 (2)
Ta1—Cl3	2.473 (2)	Cl3—Ta1^iii	2.473 (2)
Ta1—Cl4	2.474 (2)	Cl3—K^v	3.512 (3)
Ta1—Cl5	2.600 (2)	Cl3—K^vi	3.512 (3)
Ta1—Ta1^ii	2.8901 (7)	Cl4—Ta1^ii	2.474 (2)
Ta1—Ta2^i	2.8920 (5)	Cl5—K^v	3.053 (3)
Ta1—Ta1^iii	2.8944 (6)	Cl5—K^iv	3.073 (3)
Ta1—Ta2	2.9011 (5)	Cl5—K^vii	3.163 (3)
Ta2—Cl2	2.464 (2)	Cl6—K	2.992 (3)
Ta2—Cl2^ii	2.464 (2)	Cl6—K^ii	2.992 (3)
Ta2—Cl1	2.472 (2)	K—Cl5^v	3.053 (3)
Ta2—Cl1^ii	2.4720 (19)	K—Cl5^iv	3.073 (3)
Ta2—Cl6	2.553 (3)	K—Cl5^viii	3.163 (3)
Ta2—Ta1^iii	2.8920 (5)	K—Cl1^iv	3.359 (3)
Ta2—Ta1^i	2.8920 (5)	K—Cl3^v	3.512 (3)
Ta2—Ta1^ii	2.9011 (5)	K—K^ix	4.452 (5)
Cl1—K^iv	3.359 (3)	K—K^x	4.715 (5)
Cl2^i—Ta1—Cl1	161.60 (7)	Cl1—Ta2—Ta1^ii	96.39 (5)
Cl2^i—Ta1—Cl3	88.47 (5)	Cl1^ii—Ta2—Ta1^ii	53.99 (5)
Cl1—Ta1—Cl3	88.09 (6)	Cl6—Ta2—Ta1^ii	134.91 (5)
Cl2^i—Ta1—Cl4	89.31 (8)	Ta1^iii—Ta2—Ta1^ii	89.831 (15)
Cl1—Ta1—Cl4	88.25 (9)	Ta1^i—Ta2—Ta1^ii	59.952 (14)
Cl3—Ta1—Cl4	161.54 (5)	Ta1—Ta2—Ta1^ii	59.750 (16)
Cl2^i—Ta1—Cl5	80.35 (7)	Ta1—Cl1—Ta2	71.91 (5)
Cl1—Ta1—Cl5	81.26 (7)	Ta1—Cl1—K^iv	98.91 (7)
Cl3—Ta1—Cl5	81.02 (6)	Ta2—Cl1—K^iv	149.88 (10)
Cl4—Ta1—Cl5	80.54 (6)	Ta1—Cl1—K	153.94 (8)
Cl2^i—Ta1—Ta1^ii	96.60 (5)	Ta2—Cl1—K	95.43 (7)
Cl1—Ta1—Ta1^ii	96.75 (5)	K^iv—Cl1—K	102.69 (8)
Cl3—Ta1—Ta1^ii	144.18 (4)	Ta1^i—Cl2—Ta2	72.02 (5)
Cl4—Ta1—Ta1^ii	54.27 (3)	Ta1^iii—Cl3—Ta1	71.64 (8)
Cl5—Ta1—Ta1^ii	134.79 (5)	Ta1^iii—Cl3—K^v	149.85 (6)
Cl2^i—Ta1—Ta2^i	54.13 (5)	Ta1—Cl3—K^v	97.30 (4)
Cl1—Ta1—Ta2^i	144.26 (5)	Ta1^iii—Cl3—K^vi	97.30 (4)
Cl3—Ta1—Ta2^i	96.55 (3)	Ta1—Cl3—K^vi	149.85 (5)
Cl4—Ta1—Ta2^i	96.97 (5)	K^v—Cl3—K^vi	104.60 (11)
Cl5—Ta1—Ta2^i	134.48 (5)	Ta1^ii—Cl4—Ta1	71.46 (7)
Ta1^ii—Ta1—Ta2^i	60.022 (8)	Ta1—Cl5—K^v	106.74 (8)
Cl2^i—Ta1—Ta1^iii	96.53 (5)	Ta1—Cl5—K^iv	103.53 (8)
Cl1—Ta1—Ta1^iii	96.08 (5)	K^v—Cl5—K^iv	142.03 (9)
Cl3—Ta1—Ta1^iii	54.18 (4)	Ta1—Cl5—K^vii	111.62 (9)
Cl4—Ta1—Ta1^iii	144.26 (3)	K^v—Cl5—K^vii	91.47 (8)
Cl5—Ta1—Ta1^iii	135.20 (5)	K^iv—Cl5—K^vii	98.23 (8)
Ta1^ii—Ta1—Ta1^iii	90.0	Ta2—Cl6—K	114.99 (7)
Ta2^i—Ta1—Ta1^iii	60.179 (13)	Ta2—Cl6—K^ii	114.99 (7)
Cl2^i—Ta1—Ta2	144.30 (5)	K—Cl6—K^ii	125.78 (13)
Cl1—Ta1—Ta2	54.10 (5)	Cl6—K—Cl5^v	112.70 (10)
Cl3—Ta1—Ta2	96.32 (3)	Cl6—K—Cl5^iv	128.03 (11)
Cl4—Ta1—Ta2	96.15 (5)	Cl5^v—K—Cl5^iv	119.01 (9)
Cl5—Ta1—Ta2	135.35 (5)	Cl6—K—Cl5^viii	109.81 (11)
Ta1^ii—Ta1—Ta2	60.125 (8)	Cl5^v—K—Cl5^viii	88.53 (8)
Ta2^i—Ta1—Ta2	90.169 (15)	Cl5^iv—K—Cl5^viii	77.26 (8)
Ta1^iii—Ta1—Ta2	59.869 (14)	Cl6—K—Cl1^iv	85.85 (10)
Cl2—Ta2—Cl2^ii	89.02 (10)	Cl5^v—K—Cl1^iv	124.14 (10)
Cl2—Ta2—Cl1	162.33 (7)	Cl5^iv—K—Cl1^iv	61.59 (7)
Cl2^ii—Ta2—Cl1	88.21 (7)	Cl5^viii—K—Cl1^iv	135.87 (9)
Cl2—Ta2—Cl1^ii	88.21 (7)	Cl6—K—Cl3^v	116.78 (10)
Cl2^ii—Ta2—Cl1^ii	162.33 (7)	Cl5^v—K—Cl3^v	59.81 (6)
Cl1—Ta2—Cl1^ii	89.16 (11)	Cl5^iv—K—Cl3^v	86.20 (7)
Cl2—Ta2—Cl6	81.42 (7)	Cl5^viii—K—Cl3^v	130.71 (10)
Cl2^ii—Ta2—Cl6	81.42 (7)	Cl1^iv—K—Cl3^v	64.76 (6)
Cl1—Ta2—Cl6	80.92 (7)	Cl6—K—Cl1	56.52 (8)
Cl1^ii—Ta2—Cl6	80.92 (7)	Cl5^v—K—Cl1	78.62 (8)
Cl2—Ta2—Ta1^iii	96.35 (5)	Cl5^iv—K—Cl1	129.01 (8)
Cl2^ii—Ta2—Ta1^iii	53.85 (5)	Cl5^viii—K—Cl1	153.73 (9)
Cl1—Ta2—Ta1^iii	96.07 (5)	Cl1^iv—K—Cl1	69.11 (7)
Cl1^ii—Ta2—Ta1^iii	143.82 (5)	Cl3^v—K—Cl1	60.82 (6)
Cl6—Ta2—Ta1^iii	135.26 (5)	Cl6—K—K^ix	120.36 (11)
Cl2—Ta2—Ta1^i	53.85 (5)	Cl5^v—K—K^ix	45.25 (6)
Cl2^ii—Ta2—Ta1^i	96.35 (5)	Cl5^iv—K—K^ix	100.13 (9)
Cl1—Ta2—Ta1^i	143.82 (5)	Cl5^viii—K—K^ix	43.28 (6)
Cl1^ii—Ta2—Ta1^i	96.07 (5)	Cl1^iv—K—K^ix	153.47 (12)
Cl6—Ta2—Ta1^i	135.26 (5)	Cl3^v—K—K^ix	96.81 (9)
Ta1^iii—Ta2—Ta1^i	59.956 (17)	Cl1—K—K^ix	120.12 (9)
Cl2—Ta2—Ta1	143.67 (5)	Cl6—K—K^x	113.41 (7)
Cl2^ii—Ta2—Ta1	96.16 (5)	Cl5^v—K—K^x	119.78 (7)
Cl1—Ta2—Ta1	53.99 (5)	Cl5^iv—K—K^x	41.60 (6)
Cl1^ii—Ta2—Ta1	96.39 (5)	Cl5^viii—K—K^x	40.17 (5)
Cl6—Ta2—Ta1	134.91 (5)	Cl1^iv—K—K^x	95.71 (7)
Ta1^iii—Ta2—Ta1	59.952 (14)	Cl3^v—K—K^x	123.60 (7)
Ta1^i—Ta2—Ta1	89.831 (15)	Cl1—K—K^x	161.33 (7)
Cl2—Ta2—Ta1^ii	96.16 (5)	K^ix—K—K^x	78.33 (7)
Cl2^ii—Ta2—Ta1^ii	143.68 (5)

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