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The crystal structure of the glaserite-related compound dithallium(I)–molybdate(VI), which at 293 K crystallizes monoclinic, space group
C121 with lattice parameters
a = 10.565 (3),
b = 6.418 (1),
c = 8.039 (2) Å, β = 91.05 (4)°, has been determined. The structure was refined as an inversion twin to a final
R(
Fall) value of 0.0611 for 1006 unique reflections [
R(
Fobs) = 0.0285 for 644 observed reflections]. Second-harmonic generation measurements led to a value of
deff = 5.5 ± 0.5 pm V
−1 as an estimation of the second-harmonic conversion efficiency at phase matching. Symmetry mode analysis shows that, in general, primary modes have the highest amplitudes, yet surprisingly some of the secondary modes assume amplitudes of comparable magnitude. A comparison of the phase at 293 K with that at 350 K (space group
Pm1) shows that the main change can be described as a rotation of the molybdate tetrahedra around the trigonal
a(
b) axis. The molybdate tetrahedra as well as the octahedra around one of the symmetry-independent Tl atoms are more strongly distorted in the monoclinic phase. The coordination number for the other two Tl atoms is decreased from 12 and 10 in the high-symmetry phase to 10 and 9 in the monoclinic phase. Furthermore, the number of common edges between the Tl and Mo coordination polyhedra is reduced and the common face which is observed between them in the high-temperature phase is changed to a common edge in the low-temperature phase. The contribution of the primary symmetry modes leads exactly to this change in the coordination spheres of the atoms.
Supporting information
Data collection: STOE IPDS Software; cell refinement: STOE IPDS Software; data reduction: STOE IPDS Software; program(s) used to solve structure: coordinates from model; program(s) used to refine structure: SHELXL97 (Sheldrick, 1997).
Dithallium (I)-Molybdate (VI)
top
Crystal data top
MoO4Tl2 | F(000) = 944 |
Mr = 568.68 | Dx = 6.931 Mg m−3 |
Monoclinic, C2 | Mo Kα radiation, λ = 0.71069 Å |
Hall symbol: C 2y | Cell parameters from 1132 reflections |
a = 10.565 (3) Å | θ = 2.5–25.9° |
b = 6.4178 (13) Å | µ = 61.16 mm−1 |
c = 8.039 (2) Å | T = 293 K |
β = 91.05 (4)° | Hexagonal prismatic, yellow |
V = 545.0 (3) Å3 | 0.09 × 0.08 × 0.003 mm |
Z = 4 | |
Data collection top
STOE IPDS diffractometer | 644 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.057 |
Graphite monochromator | θmax = 25.9°, θmin = 2.5° |
Absorption correction: gaussian ? | h = −12→12 |
Tmin = 0.050, Tmax = 0.796 | k = −7→7 |
2138 measured reflections | l = −9→9 |
1006 independent reflections | |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Calculated w = 1/[σ2(Fo2) + (0.P)2] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.029 | (Δ/σ)max = 0.001 |
wR(F2) = 0.039 | Δρmax = 0.96 e Å−3 |
S = 0.71 | Δρmin = −0.93 e Å−3 |
1006 reflections | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
66 parameters | Extinction coefficient: 0.00092 (4) |
0 restraints | Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881 |
Primary atom site location: model | Absolute structure parameter: 0.159 (16) |
Crystal data top
MoO4Tl2 | V = 545.0 (3) Å3 |
Mr = 568.68 | Z = 4 |
Monoclinic, C2 | Mo Kα radiation |
a = 10.565 (3) Å | µ = 61.16 mm−1 |
b = 6.4178 (13) Å | T = 293 K |
c = 8.039 (2) Å | 0.09 × 0.08 × 0.003 mm |
β = 91.05 (4)° | |
Data collection top
STOE IPDS diffractometer | 1006 independent reflections |
Absorption correction: gaussian ? | 644 reflections with I > 2σ(I) |
Tmin = 0.050, Tmax = 0.796 | Rint = 0.057 |
2138 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.029 | 0 restraints |
wR(F2) = 0.039 | Δρmax = 0.96 e Å−3 |
S = 0.71 | Δρmin = −0.93 e Å−3 |
1006 reflections | Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881 |
66 parameters | Absolute structure parameter: 0.159 (16) |
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 | x | y | z | Uiso*/Ueq | |
Tl1 | 0.0000 | 0.0000 | 0.0000 | 0.0300 (5) | |
Tl2 | 0.0000 | 0.0506 (3) | 0.5000 | 0.0309 (5) | |
Tl3 | 0.33358 (12) | 0.0071 (4) | 0.17767 (15) | 0.0377 (5) | |
Mo1 | 0.6623 (2) | 0.0257 (5) | 0.3081 (2) | 0.0172 (6) | |
O1 | 0.6911 (15) | −0.0510 (19) | 0.5099 (15) | 0.051 (4) | |
O2 | 0.5627 (17) | 0.2330 (18) | 0.2873 (18) | 0.048 (5) | |
O3 | 0.8026 (14) | 0.080 (2) | 0.2167 (18) | 0.051 (4) | |
O4 | 0.5837 (17) | −0.1848 (19) | 0.2007 (18) | 0.047 (5) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Tl1 | 0.0328 (9) | 0.0296 (13) | 0.0278 (8) | 0.000 | 0.0034 (7) | 0.000 |
Tl2 | 0.0428 (10) | 0.0265 (11) | 0.0235 (9) | 0.000 | 0.0004 (8) | 0.000 |
Tl3 | 0.0369 (6) | 0.0490 (11) | 0.0272 (7) | 0.0030 (7) | −0.0023 (5) | 0.0007 (9) |
Mo1 | 0.0197 (11) | 0.0161 (17) | 0.0157 (12) | 0.0017 (10) | 0.0008 (10) | 0.0026 (14) |
O1 | 0.090 (13) | 0.049 (7) | 0.014 (7) | 0.007 (8) | −0.011 (8) | −0.004 (6) |
O2 | 0.068 (13) | 0.044 (7) | 0.032 (10) | 0.040 (7) | −0.019 (9) | −0.021 (6) |
O3 | 0.037 (10) | 0.069 (8) | 0.049 (10) | −0.015 (7) | 0.015 (8) | −0.010 (7) |
O4 | 0.065 (13) | 0.049 (9) | 0.029 (11) | −0.016 (8) | 0.022 (10) | 0.000 (6) |
Geometric parameters (Å, º) top
Tl1—O4i | 2.725 (12) | Mo1—O2 | 1.702 (13) |
Tl1—O4ii | 2.725 (12) | Mo1—O3 | 1.702 (14) |
Tl1—O3iii | 2.789 (14) | Mo1—O1 | 1.717 (12) |
Tl1—O3iv | 2.789 (14) | Mo1—O4 | 1.798 (13) |
Tl1—Tl3 | 3.7784 (18) | O1—Tl3viii | 2.557 (13) |
Tl1—Tl3v | 3.7784 (18) | O2—Tl2ix | 2.749 (12) |
Tl2—O2vi | 2.749 (12) | O3—Tl3ix | 2.781 (13) |
Tl2—O2vii | 2.749 (12) | O3—Tl1x | 2.789 (14) |
Tl3—O1viii | 2.557 (13) | O4—Tl1xi | 2.725 (12) |
Tl3—O3vi | 2.781 (13) | | |
| | | |
O4i—Tl1—O4ii | 84.1 (7) | O1viii—Tl3—O3vi | 74.4 (4) |
O4i—Tl1—O3iii | 89.7 (4) | O1viii—Tl3—Tl1 | 105.0 (4) |
O4ii—Tl1—O3iii | 74.5 (4) | O3vi—Tl3—Tl1 | 85.4 (3) |
O4i—Tl1—O3iv | 74.5 (4) | O2—Mo1—O3 | 109.9 (8) |
O4ii—Tl1—O3iv | 89.7 (4) | O2—Mo1—O1 | 114.5 (7) |
O3iii—Tl1—O3iv | 158.9 (5) | O3—Mo1—O1 | 109.0 (7) |
O4i—Tl1—Tl3 | 58.5 (4) | O2—Mo1—O4 | 105.1 (7) |
O4ii—Tl1—Tl3 | 120.3 (4) | O3—Mo1—O4 | 110.1 (7) |
O3iii—Tl1—Tl3 | 62.0 (3) | O1—Mo1—O4 | 108.1 (7) |
O3iv—Tl1—Tl3 | 117.7 (3) | Mo1—O1—Tl3viii | 150.1 (7) |
O4i—Tl1—Tl3v | 120.3 (4) | Mo1—O2—Tl2ix | 132.4 (7) |
O4ii—Tl1—Tl3v | 58.5 (4) | Mo1—O3—Tl3ix | 110.7 (6) |
O3iii—Tl1—Tl3v | 117.7 (3) | Mo1—O3—Tl1x | 154.1 (7) |
O3iv—Tl1—Tl3v | 62.0 (3) | Tl3ix—O3—Tl1x | 91.1 (4) |
Tl3—Tl1—Tl3v | 178.63 (7) | Mo1—O4—Tl1xi | 169.8 (8) |
O2vi—Tl2—O2vii | 84.3 (7) | | |
Symmetry codes: (i) x−1/2, y+1/2, z; (ii) −x+1/2, y+1/2, −z; (iii) −x+1, y, −z; (iv) x−1, y, z; (v) −x, y, −z; (vi) x−1/2, y−1/2, z; (vii) −x+1/2, y−1/2, −z+1; (viii) −x+1, y, −z+1; (ix) x+1/2, y+1/2, z; (x) x+1, y, z; (xi) x+1/2, y−1/2, z. |
Experimental details
Crystal data |
Chemical formula | MoO4Tl2 |
Mr | 568.68 |
Crystal system, space group | Monoclinic, C2 |
Temperature (K) | 293 |
a, b, c (Å) | 10.565 (3), 6.4178 (13), 8.039 (2) |
β (°) | 91.05 (4) |
V (Å3) | 545.0 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 61.16 |
Crystal size (mm) | 0.09 × 0.08 × 0.003 |
|
Data collection |
Diffractometer | STOE IPDS diffractometer |
Absorption correction | Gaussian |
Tmin, Tmax | 0.050, 0.796 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2138, 1006, 644 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.615 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.039, 0.71 |
No. of reflections | 1006 |
No. of parameters | 66 |
Δρmax, Δρmin (e Å−3) | 0.96, −0.93 |
Absolute structure | Flack H D (1983), Acta Cryst. A39, 876-881 |
Absolute structure parameter | 0.159 (16) |
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