Tb2Mo4O15

inorganic papers

i106

Structure Reports Online

ISSN 1600-5368

Tb2Mo4O15

Haruo Naruke* and Toshihiro Yamase

Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan

Correspondence e-mail: [email protected]

Key indicators Single-crystal X-ray study T= 296 K

Mean(Mo±O) = 0.004 AÊ Rfactor = 0.023 wRfactor = 0.060

Data-to-parameter ratio = 15.7

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2001 International Union of Crystallography Printed in Great Britain ± all rights reserved

The title compound, tetramolybdenum(VI) diterbate(III), was prepared by pyrolysis of Tb2(H2O)12Mo8O276H2O at 1023 K

for 2 h in air. The structure consists of trigonal bipyramidal MoO5, tetrahedral MoO4, and monocapped trigonal prismatic

TbO7units. The two MoO5and two MoO4units are

corner-shared, to form a Mo4O15group.

Comment

Much attention has been paid to the physical properties of rare earth (RE) molybdates: for example, the ferroelectric and ferroelastic properties of Gd2(MoO4)3 (Borchardt &

Bier-stedt, 1966), fast oxide-ion conduction in La2Mo2O9(Lacorre

et al., 2000), trivalent scandium conduction in Sc2(MoO4)3

(Imanakaet al., 2000), and unusual negative thermal expan-sion for RE2(MoO4)3(Evanset al., 1997). RE molybdates are

usually prepared by ®ring stoichiometric mixtures of RE2O3

and MoO3. However, because of the strong vaporization

behavior of MoO3(>1043 K), it is not easy to maintain their

initial stoichiometry. For this reason, although many nRE2O3mMoO3phases are found in equilibrium studies, only

a few compounds have been crystallized and their structures determined. Recently, we obtained single crystals of novel europium molybdates, Eu4Mo7O27 (n:m = 2:7) and

Eu6Mo10O39 (3:10), in a melt of Eu2O36MoO3, by 1073 K

pyrolysis of an Mo-rich precursor Eu2(H2O)12Mo8O276H2O

(= Eu2O38MoO318H2O) (Naruke & Yamase, 2001). We

applied this preparation method to synthesize nTb2O3

-mMoO3phases, and obtained single crystals of Tb2Mo4O15.

Tb2Mo4O15 is isomorphous with Ho2Mo4O15 (Efremov et

al., 1988). Fig. 1ashows the coordination environment of the Tb, Mo1, and Mo2 atoms. The Tb atom is coordinated by seven O atoms with a mean TbÐO distance of 2.330 AÊ, which is slightly longer than the HoÐO distance (mean 2.305 AÊ) in Ho2Mo4O15(Efremovet al., 1988), as a result of the difference

in the ionic radii of Tb3+_{and Ho}3+_{(Shannon, 1976). The TbO} 7

polyhedron is approximated to a monocapped trigonal prism, comprising two trigonal planes of [O2iii_{, O4, O7}iv_{] and [O3,}

O6i_{, O8}ii_{], and a capping O5}v_{atom. As shown in Fig. 1(b), the}

resulting Mo1O5and Mo2O4polyhedra share a corner at the

O2 atom. Furthermore, Mo1O5 and the symmetry-related

Mo1vii_O

5 are corner-shared by the O1 atom which lies on a

center of symmetry. As a result, the molybdate polyhedra form a tetrameric Mo4O15 cluster (Fig. 1b). In the Mo1O5

poly-hedron, the Mo1ÐO2vi_{bond length is much longer than the}

others (Table 1). A similar distorted MoO5trigonal bipyramid

has also been observed in Eu4Mo7O27 (Naruke & Yamase,

2001). It is interesting to note that Ce2Mo4O15 (Fallon &

Gatehouse, 1982) and La2Mo4O15(Duboiset al., 2001) possess

different molybdate groups ({Mo4O14}1and Mo6O22groups,

respectively) and coordination numbers of the RE (8 and 9, respectively). The TbO7, Mo1O5 and Mo2O4 polyhedra are

connected by edge- and corner-sharing in the crystal lattice (Fig. 2).

Experimental

The precursor Tb2(H2O)12Mo8O276H2O was prepared by

modi®ca-tion of the synthesis procedure of Eu2(H2O)12Mo8O276H2O (Yamase

& Naruke, 1991). An aqueous solution (10 ml) containing MoO3

(1.93 g) and KOH (1.5 g) was diluted to 1000 ml, and acidi®ed to pH = 4.5 with HClO4. Tb(NO3)36H2O (3.8 g) was dissolved in water

(20 ml) and added slowly to the molybdate solution with stirring. The

®nal pH was adjusted to 3.0 with HClO4, and the solution was kept at

room temperature. The pale yellow polycrystalline product, obtained after a week, was collected by ®ltration, washed with water, and dried in air. Powder (0.1 g) was placed on an alumina container and ®red at 1023 K for 2 h in air. Single crystals of Tb2Mo4O15were formed in a

glassy substance. Reuse of the same container was effective in the crystallization of Tb2Mo4O15. Details of the ®ring conditions are

described in the earlier paper (Naruke & Yamase, 2001). Crystal data

Mo4O15Tb2 Mr= 941.60

Monoclinic, P21=c a= 6.8666 (4) AÊ

b= 9.6596 (3) AÊ

c= 10.5866 (5) AÊ

= 105.827 (2)

V= 675.57 (6) AÊ3 Z= 2

Dx= 4.629 Mg mÿ3

Mo Kradiation Cell parameters from 3943

re¯ections

= 3.7±27.5

= 13.97 mmÿ1 T= 296.2 K Block, colorless 0.100.100.05 mm

Data collection

Rigaku R-AXIS±RAPID Imaging Plate diffractometer

!scans

Absorption correction: numerical (Higashi, 1999a,b)

Tmin= 0.284,Tmax= 0.512 6254 measured re¯ections

1545 independent re¯ections 1454 re¯ections withF2_{> 2(F}2₎ Rint= 0.045

max= 27.5 h= 0!8

k= 0!12

l=ÿ13!13

Acta Cryst.(2001). E57, i106±i108 Naruke and Yamase Mo₄O₁₅Tb₂

i107

inorganic papers

Figure 2

Packing diagram of Tb2Mo4O15viewed parallel to theaaxis. The green

polyhedra denote the TbO7, the hatched grey polyhedra the Mo1O5, and

the plain grey tetrahedra the Mo2O4units.

Figure 1

ORTEPII (Johnson, 1976) views of the coordination environments of (a)

Tb, Mo1 and Mo2, and (b) the Mo4O15 group in Tb2Mo4O15.

Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) 2ÿx;ÿy;1ÿz; (ii) 2ÿx;1

2‡y;32ÿz; (iii)

x;ÿ1

2ÿy;12‡z; (iv) 1ÿx;yÿ12;32ÿz; (v) 2ÿx;yÿ12;32ÿz; (vi)

inorganic papers

i108

Re®nement

Re®nement onF2 R[F2_{> 2(F}2_{)] = 0.023} wR(F2_{) = 0.060} S= 0.90 1543 re¯ections 98 parameters

w= 1/[2_(F

o2) + {0.05[max(Fo2,0)

+ 2Fc2]/3}2]

(/)max= 0.001

max= 1.82 e AÊÿ3

min=ÿ1.97 e AÊÿ3

Extinction correction: Zachariasen (1967) type 2 Gaussian isotropic Extinction coef®cient: 0.052 (1)

Table 1

Selected interatomic distances (AÊ).

TbÐO4 2.276 (3) TbÐO6i _{2.303 (3)} TbÐO8ii _{2.304 (3)} TbÐO3 2.331 (3) TbÐO2iii _{2.335 (3)} TbÐO7iv _{2.374 (4)} TbÐO5v _{2.389 (3)} Mo1ÐO3 1.728 (4) Mo1ÐO5 1.736 (3)

Mo1ÐO7 1.749 (3) Mo1ÐO1 1.8695 (3) Mo1ÐO2vi _{2.544 (3)} Mo2ÐO6 1.747 (3) Mo2ÐO8 1.752 (4) Mo2ÐO4 1.760 (3) Mo2ÐO2 1.782 (3) Mo2ÐO5i _{3.211 (4)}

Symmetry codes: (i) 2ÿx;ÿy;1ÿz; (ii) 2ÿx;1

2‡y;32ÿz; (iii)x;ÿ12ÿy;12‡z; (iv)

1ÿx;yÿ1_2;3

2ÿz; (v) 2ÿx;yÿ12;32ÿz; (vi) 1ÿx;ÿy;1ÿz.

Difference Fourier peaks with max = 1.82 and min =

ÿ1.97 e AÊÿ3_{are observed at positions 0.744 and 0.038 AÊ from the Tb}

atom, respectively.

Data collection: PROCESS-AUTO (Rigaku, 1998); cell re®ne-ment: PROCESS-AUTO; data reduction: TEXSAN (Molecular Structure Corporation, 2000; program(s) used to solve structure: SIR92 (Altomareet al., 1994); program(s) used to re®ne structure: TEXSAN; software used to prepare material for publication: TEXSAN.

This work was supported in part by Grant-in-Aid for Scienti®c Research (Nos. 10304055 and 1274036) from the Ministry of Education, Culture, Sports, Science, and Tech-nology.

References

Altomare, A., Cacarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994).J. Appl. Cryst.27, 435.

Borchardt, H. J. & Bierstedt, P. E. (1966).Appl. Phys. Lett.8, 50±52. Dubois, F., Goutenoire, F., Laligant, Y., Suard, E. & Lacorre, P. (2001).J. Solid

State Chem.159, 228±233.

Efremov, V. A., Davydova, N. N., Gokhman, L. Z., Evdokimov, A. A. & Trunov, V. K. (1988).Russ. J. Inorg. Chem.33, 1732±1735.

Evans, J. S. O., Marry, T. A. & Sleight, A. W. (1997).J. Solid State Chem.133, 580±583.

Fallon, G. D. & Gatehouse, B. M. (1982).J. Solid State Chem.44, 156±161. Higashi, T. (1999a).SHAPE. Rigaku Corporation, Tokyo, Japan. Higashi, T. (1999b).NUMABS. Rigaku Corporation, Tokyo, Japan. Imanaka, N., Ueda, T., Okazaki, Y., Tamura, S. & Adachi, G. (2000).Chem.

Mater.12, 1910±1913.

Johnson, C. K. (1976).ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.

Lacorre, P., Goutenoire, F., Bohnke, O., Retoux, R. & Laligant, Y. (2000).

Nature (London),404, 856±858.

Molecular Structure Corporation (2000).TEXSAN.Version 1.11. MSC, 9009 New Trails Drive, The Woodlands, TX 77381±5209, USA.

Naruke, H. & Yamase, T. (2001).J. Solid State Chem.In the press. Rigaku (1998).PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan. Shannon, R. D. (1976).Acta Cryst.A32, 751±767.

supporting information

sup-1 Acta Cryst. (2001). E57, i106–i108

supporting information

Acta Cryst. (2001). E57, i106–i108 [https://doi.org/10.1107/S1600536801018517]

Tb

Mo

O

Haruo Naruke and Toshihiro Yamase

(I)

Crystal data Mo4O15Tb2

Mr = 941.60

Monoclinic, P21/c

a = 6.8666 (4) Å b = 9.6596 (3) Å c = 10.5866 (5) Å β = 105.827 (2)° V = 675.57 (6) Å3

Z = 2

F(000) = 836 Dx = 4.629 Mg m−3

Mo Kα radiation, λ = 0.7107 Å Cell parameters from 3943 reflections θ = 3.7–27.5°

µ = 13.97 mm−1

T = 296 K Block, colorless 0.10 × 0.10 × 0.05 mm

Data collection

Rigaku RAXIS-RAPID Imaging Plate diffractometer

Detector resolution: 10.00 pixels mm-1

ω scans

Absorption correction: numerical (Higashi, 1999a,b)

Tmin = 0.284, Tmax = 0.512

6254 measured reflections

1545 independent reflections 1454 reflections with F2 _{> 2.0σ(F}2₎

Rint = 0.045

θmax = 27.5°

h = 0→8 k = 0→12 l = −13→13

Refinement Refinement on F2

R[F2 _{> 2σ(F}2_{)] = 0.023}

wR(F2_{) = 0.060}

S = 0.90 1543 reflections 98 parameters

w = 1/[σ2_(F

o2) + (0.05000(Max(Fo2,0) +

2Fc2)/3)2]

(Δ/σ)max = 0.001

Δρmax = 1.82 e Å−3

Δρmin = −1.97 e Å−3

Extinction correction: Zachariasen(1967) type 2 Gaussian isotropic

Extinction coefficient: 0.052 (1)

Special details

Refinement. Refinement using reflections with F2 _{> -10.0 σ(F}2_{). 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 F}2 _{> 2.0 σ(F}2_{) is used only for calculating R-factor}

(gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2₎

x y z Uiso*/Ueq

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sup-2 Acta Cryst. (2001). E57, i106–i108

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 (Å2₎

U11 _U22 _U33 _U12 _U13 _U23

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—O6i _{2.303 (3) Mo1—O1 1.8695 (3)}

Tb—O8ii _{2.304 (3) Mo1—O2}vi _{2.544 (3)}

Tb—O3 2.331 (3) Mo2—O6 1.747 (3)

Tb—O2iii _{2.335 (3) Mo2—O8 1.752 (4)}

Tb—O7iv _{2.374 (4) Mo2—O4 1.760 (3)}

Tb—O5v _{2.389 (3) Mo2—O2 1.782 (3)}

Mo1—O3 1.728 (4) Mo2—O5i _{3.211 (4)}

Mo1—O5 1.736 (3)

O4—Tb—O6i _{82.9 (1) O2}iii_—Tb—O5v _{75.2 (1)}

O4—Tb—O8ii _{162.6 (1) O7}iv_—Tb—O5v _{142.1 (1)}

O4—Tb—O3 118.9 (1) O3—Mo1—O5 103.9 (2)

O4—Tb—O2iii _{90.2 (1) O3—Mo1—O7 113.7 (2)}

O4—Tb—O7iv _{87.5 (1) O3—Mo1—O1 115.7 (1)}

O4—Tb—O5v _{83.2 (1) O3—Mo1—O2}vi _{79.3 (1)}

O6i_—Tb—O8ii _{95.6 (1) O5—Mo1—O7 105.3 (2)}

O6i_{—Tb—O3 76.2 (1) O5—Mo1—O1 103.3 (1)}

O6i_—Tb—O2iii _{149.8 (1) O5—Mo1—O2}vi _{176.8 (2)}

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sup-3 Acta Cryst. (2001). E57, i106–i108

O6i_—Tb—O5v _{74.8 (1) O7—Mo1—O2}vi _{73.2 (1)}

O8ii_{—Tb—O3 77.2 (1) O1—Mo1—O2}vi _{75.07 (8)}

O8ii_—Tb—O2iii _{82.5 (1) O6—Mo2—O8 108.8 (2)}

O8ii_—Tb—O7iv _{104.1 (1) O6—Mo2—O4 110.3 (2)}

O8ii_—Tb—O5v _{79.8 (1) O6—Mo2—O2 110.4 (2)}

O3—Tb—O2iii _{131.7 (1) O8—Mo2—O4 108.0 (2)}

O3—Tb—O7iv _{75.1 (1) O8—Mo2—O2 109.9 (2)}

O3—Tb—O5v _{140.6 (1) O4—Mo2—O2 109.4 (2)}

O2iii_—Tb—O7iv _{68.1 (1)}