Tb₂Mo₄O₁₅

The title compound, tetramolybdenum(VI) diterbate(III), was prepared by pyrolysis of Tb₂(H₂O)₁₂Mo₈O₂₇·6H₂O at 1023 K for 2 h in air. The structure consists of trigonal bipyramidal MoO₅, tetrahedral MoO₄, and monocapped trigonal prismatic TbO₇ units. The two MoO₅ and two MoO₄ units are corner-shared, to form a Mo₄O₁₅ group.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](Mo-O) = 0.004 Å
• R factor = 0.023
• wR factor = 0.060
• Data-to-parameter ratio = 15.7

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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Computing details

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO; data reduction: TEXSAN (Molecular Structure Corporation, 2000; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: TEXSAN; software used to prepare material for publication: TEXSAN.

(I)

Crystal data

Mo4O15Tb2	F(000) = 836
Mr = 941.60	Dx = 4.629 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.7107 Å
a = 6.8666 (4) Å	Cell parameters from 3943 reflections
b = 9.6596 (3) Å	θ = 3.7–27.5°
c = 10.5866 (5) Å	µ = 13.97 mm^−1
β = 105.827 (2)°	T = 296 K
V = 675.57 (6) Å^3	Block, colorless
Z = 2	0.10 × 0.10 × 0.05 mm

Data collection

Rigaku RAXIS-RAPID Imaging Plate diffractometer	1454 reflections with F^2 > 2.0σ(F^2)
Detector resolution: 10.00 pixels mm^-1	Rint = 0.045
ω scans	θmax = 27.5°
Absorption correction: numerical (Higashi, 1999a,b)	h = 0→8
Tmin = 0.284, Tmax = 0.512	k = 0→12
6254 measured reflections	l = −13→13
1545 independent reflections

Refinement

Refinement on F^2	w = 1/[σ^2(Fo^2) + (0.05000(Max(Fo^2,0) + 2Fc^2)/3)^2]
R[F^2 > 2σ(F^2)] = 0.023	(Δ/σ)max = 0.001
wR(F^2) = 0.060	Δρmax = 1.82 e Å^−3
S = 0.90	Δρmin = −1.97 e Å^−3
1543 reflections	Extinction correction: Zachariasen(1967) type 2 Gaussian isotropic
98 parameters	Extinction coefficient: 0.052 (1)

Special details

Refinement. Refinement using reflections with F² > -10.0 σ(F²). The weighted R-factor (wR) and goodness of fit (S) are based on F². R-factor (gt) are based on F. The threshold expression of F² > 2.0 σ(F²) is used only for calculating R-factor (gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Tb	0.78645 (3)	0.02347 (2)	0.72258 (2)	0.00878 (8)
Mo1	0.62161 (6)	0.40522 (4)	0.65547 (4)	0.0101 (1)
Mo2	0.91738 (6)	−0.24357 (4)	0.48824 (4)	0.0097 (1)
O1	0.5000	0.5000	0.5000	0.023 (1)
O2	0.7563 (5)	−0.3652 (4)	0.3829 (3)	0.0165 (8)
O3	0.6110 (5)	0.2267 (4)	0.6456 (3)	0.0175 (8)
O4	0.7783 (6)	−0.1534 (4)	0.5792 (4)	0.0199 (9)
O5	0.8769 (5)	0.4423 (4)	0.6818 (4)	0.0192 (8)
O6	1.0193 (6)	−0.1280 (4)	0.3965 (4)	0.0200 (9)
O7	0.5571 (6)	0.4720 (4)	0.7922 (4)	0.0188 (9)
O8	1.1158 (6)	−0.3305 (4)	0.5992 (3)	0.0208 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Tb	0.0097 (2)	0.0078 (2)	0.0091 (2)	0.00022 (7)	0.00296 (9)	0.00045 (7)
Mo1	0.0090 (2)	0.0097 (2)	0.0111 (2)	0.0008 (1)	0.0016 (1)	0.0003 (1)
Mo2	0.0123 (2)	0.0090 (2)	0.0083 (2)	−0.0015 (1)	0.0034 (1)	−0.0001 (1)
O1	0.017 (3)	0.029 (3)	0.023 (2)	0.006 (2)	0.004 (2)	0.019 (2)
O2	0.015 (2)	0.019 (2)	0.014 (2)	−0.002 (1)	0.002 (1)	−0.007 (1)
O3	0.015 (2)	0.010 (1)	0.024 (2)	0.004 (1)	0.000 (1)	0.000 (1)
O4	0.024 (2)	0.017 (2)	0.023 (2)	−0.005 (1)	0.013 (1)	−0.013 (1)
O5	0.011 (1)	0.024 (2)	0.022 (2)	−0.003 (1)	0.004 (1)	−0.006 (2)
O6	0.020 (2)	0.019 (2)	0.025 (2)	0.001 (1)	0.013 (1)	0.007 (1)
O7	0.014 (2)	0.025 (2)	0.017 (2)	0.000 (1)	0.004 (1)	−0.010 (1)
O8	0.021 (2)	0.021 (2)	0.017 (2)	−0.001 (1)	−0.002 (1)	0.007 (1)

Geometric parameters (Å, º)

Tb—O4	2.276 (3)	Mo1—O7	1.749 (3)
Tb—O6^i	2.303 (3)	Mo1—O1	1.8695 (3)
Tb—O8^ii	2.304 (3)	Mo1—O2^vi	2.544 (3)
Tb—O3	2.331 (3)	Mo2—O6	1.747 (3)
Tb—O2^iii	2.335 (3)	Mo2—O8	1.752 (4)
Tb—O7^iv	2.374 (4)	Mo2—O4	1.760 (3)
Tb—O5^v	2.389 (3)	Mo2—O2	1.782 (3)
Mo1—O3	1.728 (4)	Mo2—O5^i	3.211 (4)
Mo1—O5	1.736 (3)
O4—Tb—O6^i	82.9 (1)	O2^iii—Tb—O5^v	75.2 (1)
O4—Tb—O8^ii	162.6 (1)	O7^iv—Tb—O5^v	142.1 (1)
O4—Tb—O3	118.9 (1)	O3—Mo1—O5	103.9 (2)
O4—Tb—O2^iii	90.2 (1)	O3—Mo1—O7	113.7 (2)
O4—Tb—O7^iv	87.5 (1)	O3—Mo1—O1	115.7 (1)
O4—Tb—O5^v	83.2 (1)	O3—Mo1—O2^vi	79.3 (1)
O6^i—Tb—O8^ii	95.6 (1)	O5—Mo1—O7	105.3 (2)
O6^i—Tb—O3	76.2 (1)	O5—Mo1—O1	103.3 (1)
O6^i—Tb—O2^iii	149.8 (1)	O5—Mo1—O2^vi	176.8 (2)
O6^i—Tb—O7^iv	140.3 (1)	O7—Mo1—O1	113.3 (1)
O6^i—Tb—O5^v	74.8 (1)	O7—Mo1—O2^vi	73.2 (1)
O8^ii—Tb—O3	77.2 (1)	O1—Mo1—O2^vi	75.07 (8)
O8^ii—Tb—O2^iii	82.5 (1)	O6—Mo2—O8	108.8 (2)
O8^ii—Tb—O7^iv	104.1 (1)	O6—Mo2—O4	110.3 (2)
O8^ii—Tb—O5^v	79.8 (1)	O6—Mo2—O2	110.4 (2)
O3—Tb—O2^iii	131.7 (1)	O8—Mo2—O4	108.0 (2)
O3—Tb—O7^iv	75.1 (1)	O8—Mo2—O2	109.9 (2)
O3—Tb—O5^v	140.6 (1)	O4—Mo2—O2	109.4 (2)
O2^iii—Tb—O7^iv	68.1 (1)

Symmetry codes: (i) −x+2, −y, −z+1; (ii) −x+2, y+1/2, −z+3/2; (iii) x, −y−1/2, z+1/2; (iv) −x+1, y−1/2, −z+3/2; (v) −x+2, y−1/2, −z+3/2; (vi) −x+1, −y, −z+1.