research communications
The cadmium oxidotellurates(IV) Cd5(TeO3)4(NO3)2 and Cd4Te5O14
aTU Wien, Institute for Chemical Technologies and Analytics, Division of Structural Chemistry, Getreidemarkt 9/E164-05-1, 1060 Vienna, Austria
*Correspondence e-mail: matthias.weil@tuwien.ac.at
Monoclinic single crystals of Cd5(TeO3)4(NO3)2 (space group P21/c), pentacadmium tetrakis[oxidotellurate(IV)] dinitrate, and of Cd4Te5O14 (space group C2/c), tetracadmium pentaoxidotellurate(IV), were obtained under the same hydrothermal conditions. Whereas the of Cd5(TeO3)4(NO3)2 is distinctively layered, that of Cd4Te5O14 exhibits a tri-periodic framework. In Cd5(TeO3)4(NO3)2, the three CdII atoms have coordination numbers (CN) of 7, 6 and 6. The two types of [CdO6] and the [CdO7] polyhedra [bond lengths range from 2.179 (3) to 2.658 (2) Å] share corners and edges, resulting in layers extending parallel to (100). Both TeIV atoms are coordinated by three oxygen atoms in a trigonal–pyramidal shape. The oxygen atoms of the isolated [TeO3] groups [bond lengths range from 1.847 (3) to 1.886 (3) Å] all are part of the cadmium–oxygen layer. The electron lone pairs ψ of the TeIV atoms are directed away from the layer on both sides. The available interlayer space is co-occupied by the nitrate group, which is directly connected with two of its O atoms to the layer whereas the third O atom is solely bonded to the N atom and points towards the adjacent layer. In Cd4Te5O14, all three unique CdII atoms are coordinated by six oxygen atoms, considering Cd—O distances from 2.235 (2) to 2.539 (2) Å. By edge- and corner-sharing, the distorted [CdO6] polyhedra form an open framework that is partially filled with three different stereochemically active TeIV atoms. All of them exhibit a CN of 4, with Te—O bonds in a range from 1.859 (2) to 2.476 (2) Å. The corresponding [TeO4] units are linked to each other by corner- and edge-sharing, forming infinite helical 1∞[Te10O28] chains extending parallel to [203]. The connectivity in the chains can be described as (⋯–⋄–⋄=⋄–⋄–⋄–⋄–⋄=⋄–⋄–⋄–⋯)n where ‘⋄’ denotes a [TeO4] unit, ‘–’ a linkage via corners and ‘=’ a linkage via edges. Such a structural motif is unprecedented in the crystal chemistry of oxidotellurate(IV) compounds.
Keywords: crystal structure; cadmium; tellurite; nitrate; layer structure; electron lone pair.
1. Chemical context
Oxidotellurates show a vast structural diversity, in particular with tellurium in the +IV et al., 2016). This variety can be attributed to the different coordination numbers (CNs) of the TeIV atom to the oxygen ligands (ranging from 3 to 5 for the first coordination sphere) and, particularly, to the 5s2 electron lone pair (ψ) localized at the TeIV atom. The large space consumption of ψ often leads to rather low-symmetric and one-sided anionic coordination polyhedra in oxidotellurates(IV), and in consequence to the formation of modular structural motifs like clusters, chains, layers, or to open-frameworks penetrated by channels (Stöger & Weil, 2013). These features can be enhanced by introducing other oxido-anion groups as spacers into the oxidotellurate(IV) framework. This concept has already proven successful for several types of oxido-anion groups, for example in the form of tetrahedral groups like in sulfates or selenates (Weil & Shirkhanlou, 2017), phosphates (Eder & Weil, 2020a), and arsenates (Missen et al., 2020), or in the form of trigonal–planar groups like in carbonates (Eder et al., 2022) and nitrates (Lee et al., 2021; Stöger & Weil, 2013).
which has been summarized and categorized recently (ChristyFor the present study, we have focused on divalent metal oxidotellurates(IV) modified by nitrate anions. For this purpose, we have used our experience with the system Ca–Te–O, for which corresponding phases such as Ca5Te4O12(NO3)2(H2O)2 and Ca6Te5O15(NO3)2 exist (Stöger & Weil, 2013). Since the ionic radii of CaII and CdII differ only slightly (Shannon, 1976), the Cd–Te–O system appears promising in this regard. In fact, we were able to hydrothermally grow single crystals of corresponding cadmium oxidotellurate(IV) nitrate phases with the composition Cd5(TeO3)4(NO3)2 and Cd4Te4O11(NO3)2 (Eder, 2023). Under the same hydrothermal conditions, single crystals of the nitrate-free compound Cd4Te5O14 were also obtained as a minor by-product, next to other impurity phases.
In the present communication we report on preparation conditions and crystal structures of Cd5(TeO3)4(NO3)2 and Cd4Te5O14. As a result of systematic and the resulting problems in the processing of the diffraction intensities, the of Cd4Te4O11(NO3)2 must be regarded as unsatisfactory. The preliminary structure model is deposited in form of a (CIF; Hall et al., 2006) and is available from the electronic supporting information (ESI) of this article.
2. Structural commentary
Cd5(TeO3)4(NO3)2
The a), all atoms are located at sites corresponding to general positions (4 e) of P21/c.
comprises two Te, three Cd, one N and nine O atoms. With the exception of Cd3 (site symmetry ; multiplicity 2, Wyckoff letterThe CdII atoms exhibit a CN of [5 + 2] for Cd1, [5 + 1] for Cd2, and 6 for Cd3 when the inner coordination sphere is comprised of oxygen atoms at distances between 2.179 (3) and 2.389 (5) Å, and the outer coordination sphere at distances between 2.524 (3) and 2.658 (2) Å (Table 1, Fig. 1). Including these remote oxygen atoms for the bond valence sum (BVS) calculations (Brown, 2002), the values for the CdII atoms amount to 1.92 (Cd1), 2.02 (Cd2) and 2.09 (Cd3) valence units (v. u.) using the parameters of Brese & O’Keeffe (1991). The mean Cd—O distances are 2.403 Å for Cd1, 2.328 Å for Cd2, and 2.295 Å for Cd3, in good agreement with literature values [2.302 (69) Å for CN = 6 from 135 coordination polyhedra, 2.377 (134) Å for CN = 7 from 6 polyhedra; Gagné & Hawthorne, 2020]. The two [CdO6] and the [CdO7] polyhedra are connected by corner- and edge-sharing and thereby form layers extending parallel to (100) (Fig. 2).
Both Te sites are coordinated by three oxygen atoms in a trigonal-pyramidal shape. If the non-bonding 5s2 electron lone pair ψ of the TeIV atoms is also taken into account, [ψTeO3] polyhedra with the shapes of flattened tetrahedra are formed. The positions of ψ were calculated with the LPLoc program (Hamani et al., 2020) resulting in the following fractional coordinates: x = 0.3787, y = 0.4979, z = 0.0221 for ψ1 at the Te1 atom (distance Te1—ψ1 = 1.195 Å), and x = 0.6617, y = 0.3689, z = 0.2780 for ψ2 at the Te2 atom (distance Te2—ψ2 = 1.202 Å). The [TeO3] units are isolated from each other with a connectivity of Q3000 according to the notation of Christy et al. (2016). The BVS values of the TeIV atoms using the parameters of Mills & Christy (2013) closely correspond to the expectation of 4 v. u., with values of 3.91 (Te1) and 4.06 (Te2) v.u.
The [TeO3] groups are part of the cadmium–oxygen layers mentioned above (Fig. 2). The electron lone pairs ψ of both TeIV atoms are directed away from the layer on both sides (Fig. 3). Next to the free electron pairs ψ, the space available between adjacent layers is partly co-occupied by the nitrate group (N1, O6, O7 and O8). The (NO3)− anion is bound to the layer by sharing an edge with the [Cd2O6] polyhedron with one shorter contact [2.389 (5) Å to O7] and one longer contact [2.587 (5) Å to O8] to the Cd2 atom. The third oxygen atom of the nitrate anion, O6, is not in the coordination sphere of any CdII atom and has a slightly shorter N—O bond length of 1.234 (5) Å compared to the other two [1.242 (6) and 1.245 (6) Å]. The average N—O bond length amounts to 1.240 Å and closely matches the literature value of 1.247 (29) Å calculated for 468 N—O bonds in the nitrate anion (Gagné & Hawthorne, 2020). The O—N—O bond angles range from 117.6 (5)° (for the O atoms sharing edges with the [Cd2O6] unit) to 121.6 (5)°, indicating a slight angular distortion. The (NO3)− group deviates from planarity, as observed for many nitrates with deviations of up to 0.02 Å (Jarosch & Zemann, 1983). In Cd5(TeO3)4(NO3)2, the root-mean-square deviation of the four atoms of the (NO3)− group is 0.0082 Å, with a deviation for N1 of −0.014 (4) Å from the plane defined by O6, O7(−x + 1, y − , −z + ) and O8. The weak binding of the nitrate group to the layers is reflected in its significantly larger displacement parameters compared to the other atoms of the network (Fig. 3).
While there are no phases isotypic with Cd5(TeO3)4(NO3)2 known so far, the calcium compound Ca5(TeO3)4(NO3)2(H2O)2 (space group Cc, Z = 4; Stöger & Weil, 2013) shows some similarities with the cadmium compound. Ca5(TeO3)4(NO3)2(H2O)2 consists of (100) [Ca–Te–O] layers that are built in the same way as the [Cd–Te–O] layers in Cd5(TeO3)4(NO3)2. This is reflected in similar lattice parameters b and c for both phases. The slightly longer axes, b = 5.7289 (7) Å and c = 17.007 (2) Å for Ca5(TeO3)4(NO3)2(H2O)2 compared to b = 5.6173 (2) Å and c = 16.6136 (7) Å for Cd5(TeO3)4(NO3)2, are primarily caused by the larger ionic radii (Shannon, 1976) of CaII (1.00 Å for CN 6, 1.06 Å for CN 7) compared to CdII (0.93 Å for CN 6, 1.03 Å for CN 7). The main differences between the two structures originate from the space between the layers. In the of Ca5(TeO3)4(NO3)2(H2O)2, the two water molecules are tightly bound to one of the CaII atoms with Ca—O bond lengths of 2.390 (9) and 2.39 (2) Å. The nitrate groups, however, are not connected that well to the framework like in the of the cadmium compound. One nitrate group shares one corner with the layer [Ca—O distance = 2.462 (11) Å], while the other (NO3)− anion is completely isolated from the layers. The more loosely bound (NO3)− group can be seen as the main reason why Ca5(TeO3)4(NO3)2(H2O)2 exhibits diffuse scattering caused by stacking disorder, which can be described by OD theory (Dornberger-Schiff & Grell-Niemann, 1961; Stöger & Weil, 2013). On the contrary, no signs of diffuse scattering were discernible in the diffraction pattern of Cd5(TeO3)4(NO3)2.
Cd4Te5O14
Of the thirteen atoms in the e), while the other ten (two Te, one Cd and seven O) all belong to general 8 f positions of C2/c.
three (Cd2, Cd3, Te3) are located at positions with 2 (4The three CdII atoms are coordinated by six O atoms with distances between 2.235 (2) and 2.539 (2) Å (Table 2). The [Cd1O6] polyhedron has a distorted trigonal-prismatic shape, while the [Cd2O6] and [Cd3O6] units have rather irregular shapes. In both cases, this might be caused by the presence of two additional oxygen contacts at distances of 2.809 (3) Å for Cd2 and of 2.860 (3) Å for Cd3, respectively. Hence, the coordination numbers of the CdII atoms are best described as 6 for Cd1 and [6 + 2] for Cd2 and Cd3 (Fig. 4) The meaningfulness to include the remote oxygen atoms is underlined by the BVS of the CdII atoms using the parameters of Brese & O’Keeffe (1991). Based on sixfold coordination, these values amount to 2.00 (Cd1), 1.79 (Cd2) and 1.71 (Cd3) v. u. The latter two values increase to 1.97 (Cd2) and 1.86 (Cd3) v. u. under consideration of the two additional oxygen atoms. Likewise, the mean Cd—O distances, 2.323 Å for Cd1 (CN = 6), 2.456 Å for Cd2 (CN = 8) and 2.497 Å for Cd3 (CN = 8), comply with literature values (for Cd—O with CN = 6 (vide supra); 2.432 (118) Å for CN = 8 from 18 polyhedra; Gagné & Hawthorne, 2020).
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The TeIV atoms are all coordinated by four oxygen atoms in bisphenoidal shapes. While for Te3 the four oxygen contacts have comparable distances, for Te1 and Te2 the coordination is better described as [3 + 1] (Table 2). It should be noted that the fourth oxygen contact of Te1 has a distance of 2.476 (2) Å to O2iii and thus is slightly above the bond-length threshold of 2.40–2.45 Å. The latter was suggested by Christy et al. (2016) to distinguish between ‘structural unit’ and ‘interstitial complex’ (Hawthorne, 2014). However, the BVS of Te1 is perfectly defined with the parameters of Brese & O’Keeffe (1991), resulting in a value of 4.00 v.u. compared to 3.74 v.u. without the fourth O atom. Hence, Te1 was considered as fourfold-coordinated as well. The BVS of the three TeIV atoms amount to 4.01 (Te1), 3.93 (Te2) and 4.00 (Te3) v.u. when applying the revised parameters (Mills & Christy, 2013). The lone-pair electrons of the TeIV atoms are stereochemically active and point away from the backbone of the bisphenoids in each case. The fractional coordinates of ψ were computed with LPLoc (Hamani et al., 2020) and amount to x = 0.14556, y = 0.07878, z = −0.02783 for ψ1 at the Te1 atom (distance Te1—ψ1 = 0.968 Å), x = 0.23325, y = 0.35725, z = 0.15340 for ψ2 at the Te2 atom (distance Te2—ψ2 = 0.932 Å), and x = 0, y = 0.85614, z = 0.25 for ψ3 at the Te3 atom (distance Te3—ψ3 = 1.356 Å).
The three [TeO4] units are connected to each other forming ∞1[Te10O24/2O16/1] chains propagating parallel to [203] (Fig. 5), corresponding to a translation of 2a + 3c. The translational period of the chain is ten TeIV atoms long and consequently the oxidotellurate(IV) chains are categorized as zehner-chains (Liebau, 1985). Using the nomenclature of Christy et al. (2016), the connectivities of the three TeIV atoms are denoted as Q1301 (Te1) and Q2200 (Te2 and Te3), with a graphical representation of (⋯–⋄–⋄=⋄–⋄–⋄–⋄–⋄=⋄–⋄–⋄–⋯), where ‘⋄’ denotes a [TeO4] unit, ‘–’ a linkage via corners and ‘=’ a linkage via edges. The chains form loops leading to the shape of an ‘∞’ when viewed along the propagating direction (Fig. 6). This structural element has not been described yet for oxidotellurates (Christy et al., 2016). The 1∞[Te10O28] chains share their oxygen atoms with the CdII atoms to form a rather dense framework structure (Fig. 7).
Unlike β-CdTe2O5 (Eder & Weil, 2020b), which is isotypic with the corresponding Ca-compound (Weil & Stöger, 2008), the of Cd4Te5O14 has no structural relationship with the two polymorphs of the corresponding Ca-compound, Ca4Te5O14. In α-Ca4Te5O14 (Weil, 2004), the TeIV atoms form branched [Te8O22] achter-single chains (⋯–(⋄–Δ)–⋄–⋄–(⋄–Δ)–⋄–⋄–⋯) as well as isolated [TeO3] (Δ) groups. The high-pressure β-polymorph (Weil et al., 2016) consists of isolated [Te3O8] (Δ–⋄–Δ) and [TeO3] (Δ) units. If a Te—O contact of 2.479 (2) Å is considered as well, two [Te3O8] units are connected to form a [Te6O16] group (Δ–⋄–⋄–⋄–⋄–Δ).
3. Synthesis and crystallization
Hydrothermal experiments were carried out at a temperature of 483 K with a reaction time of one week. The reaction containers were small Teflon vessels with an inner volume of ca. 3–4 ml. The educts, generally a total of 0.5–1 g, were weighed and mixed dry manually with a spatula in the vessels. Afterwards, water was added until the reaction container was filled to ca. 2/3 of its volume, and the mixture was manually stirred again. The Teflon containers were then placed into steel autoclaves and transferred to a preheated drying oven. Cooling was achieved within circa 3 h by taking the autoclaves out of the oven.
Initially, Cd5(TeO3)4(NO3)2 was obtained in a hydrothermal reaction starting from Cd(NO3)2(H2O)4, TeO2 and KOH (molar ratios 2:1:2). Other hydrothermal experiments aimed at the repeated synthesis of Cd5(TeO3)4(NO3)2, but started from different ratios of Cd(NO3)2(H2O)4 and either K2TeO3 or KOH and TeO2, and were performed under the described hydrothermal conditions or without any additional water. Cd5(TeO3)4(NO3)2 was obtained in seven of the twelve batches. In three of these batches, a second cadmium oxidotellurate(IV) nitrate phase with presumed composition Cd4Te4O11(NO3)2 and a likewise layered structural arrangement was obtained. of this phase was hampered by systematic and overlapping reflections. The preliminary model given in the ESI is based on overlapping intensity data of a multi-domain crystal and a primitive triclinic (Z = 2, a ≃ 9.42, b ≃ 9.43, c ≃ 9.61 Å, α ≃ 92, β ≃ 108, γ ≃ 109°).
Yet another new phase, Cd4Te5O14, was isolated in form of single crystals from one of these batches, using a molar ratio of Cd(NO3)2(H2O)4:K2TeO3 = 2:1. This phase has formed in only small amounts, because powder X-ray diffraction (PXRD) measurements of the bulk material revealed a negligible fraction of this phase relative to the other products. In all batches, phase-mixtures were present. Next to the three new compounds, Cd2Te3O9 (Weil, 2004), α-TeO2 (Thomas, 1988), β-Cd3TeO6 (Weil & Veyer, 2018) and CdTeO3 (Krämer & Brandt, 1985) could be detected in the washed products. However, some reflections could not be assigned to any of the known phases stored in the Powder Diffraction File (PDF-4; Gates-Rector & Blanton, 2019). It should also be mentioned that reflections assignable to Cd5(TeO3)4(NO3)2 exhibited a of the (n00) planes, which is not surprising since the shows an assembly of (100) layers.
Single crystals of Cd5(TeO3)4(NO3)2 are colorless and have the form of elongated plates whereas single crystals of Cd4Te5O14 are colourless and bar-shaped. Both types of crystals were manually isolated from the bulk products and subjected to single crystal X-ray studies.
4. Refinement
Crystal data, data collection and structure . Structure data of both title compounds were standardized with STRUCTURE-TIDY (Gelato & Parthé, 1987). For of Cd5(TeO3)4(NO3)2, one reflection (100) was obstructed by the beamstop and was omitted from the data.
details are summarized in Table 3
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Supporting information
https://doi.org/10.1107/S2056989024010387/pk2712sup1.cif
contains datablocks Cd4Te5O14, Cd5TeO34NO32, general. DOI:Structure factors: contains datablock Cd4Te5O14. DOI: https://doi.org/10.1107/S2056989024010387/pk2712Cd4Te5O14sup2.hkl
Structure factors: contains datablock Cd5TeO34NO32. DOI: https://doi.org/10.1107/S2056989024010387/pk2712Cd5TeO34NO32sup3.hkl
Cd4Te5O14 | F(000) = 2256 |
Mr = 1311.60 | Dx = 6.394 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 11.9074 (3) Å | Cell parameters from 8153 reflections |
b = 14.3289 (3) Å | θ = 2.4–36.6° |
c = 8.7169 (2) Å | µ = 16.73 mm−1 |
β = 113.629 (1)° | T = 296 K |
V = 1362.58 (6) Å3 | Fragment, colourless |
Z = 4 | 0.09 × 0.07 × 0.06 mm |
Bruker APEXII CCD diffractometer | 3084 reflections with I > 2σ(I) |
ω– and φ–scan | Rint = 0.027 |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | θmax = 36.6°, θmin = 2.8° |
Tmin = 0.595, Tmax = 0.747 | h = −19→19 |
18799 measured reflections | k = −23→23 |
3373 independent reflections | l = −14→14 |
Refinement on F2 | 106 parameters |
Least-squares matrix: full | 0 restraints |
R[F2 > 2σ(F2)] = 0.022 | w = 1/[σ2(Fo2) + (0.007P)2 + 7.0237P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.040 | (Δ/σ)max = 0.001 |
S = 1.21 | Δρmax = 1.10 e Å−3 |
3373 reflections | Δρmin = −1.52 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Cd1 | 0.32186 (2) | 0.14608 (2) | 0.44068 (2) | 0.01114 (4) | |
Cd2 | 0.000000 | 0.15438 (2) | 0.250000 | 0.01217 (5) | |
Cd3 | 0.000000 | 0.52705 (2) | 0.250000 | 0.01663 (6) | |
Te1 | 0.15063 (2) | 0.02884 (2) | 0.04951 (2) | 0.00946 (4) | |
Te2 | 0.15858 (2) | 0.33985 (2) | 0.15582 (2) | 0.01183 (4) | |
Te3 | 0.000000 | 0.76224 (2) | 0.250000 | 0.01223 (5) | |
O1 | 0.0182 (2) | 0.41329 (16) | 0.0722 (3) | 0.0174 (4) | |
O2 | 0.0618 (2) | 0.08242 (15) | 0.5194 (3) | 0.0153 (4) | |
O3 | 0.0700 (2) | 0.23908 (16) | 0.0113 (3) | 0.0174 (4) | |
O4 | 0.15288 (19) | 0.26766 (14) | 0.3340 (2) | 0.0111 (3) | |
O5 | 0.16381 (18) | 0.05898 (15) | 0.2662 (2) | 0.0115 (4) | |
O6 | 0.19537 (19) | 0.46166 (16) | 0.3662 (3) | 0.0141 (4) | |
O7 | 0.3814 (2) | 0.17177 (19) | 0.2316 (3) | 0.0214 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.01052 (8) | 0.01416 (9) | 0.00843 (8) | −0.00111 (7) | 0.00347 (6) | −0.00161 (6) |
Cd2 | 0.00833 (11) | 0.01007 (12) | 0.01683 (13) | 0.000 | 0.00370 (10) | 0.000 |
Cd3 | 0.01015 (12) | 0.01016 (12) | 0.02670 (16) | 0.000 | 0.00435 (11) | 0.000 |
Te1 | 0.00891 (7) | 0.00993 (7) | 0.00892 (7) | −0.00007 (6) | 0.00293 (5) | −0.00049 (6) |
Te2 | 0.00967 (7) | 0.01489 (8) | 0.01080 (7) | 0.00058 (6) | 0.00397 (6) | 0.00439 (6) |
Te3 | 0.01272 (11) | 0.00968 (10) | 0.01572 (11) | 0.000 | 0.00719 (9) | 0.000 |
O1 | 0.0112 (9) | 0.0151 (10) | 0.0205 (10) | 0.0015 (8) | 0.0005 (8) | 0.0000 (8) |
O2 | 0.0174 (10) | 0.0133 (9) | 0.0168 (10) | 0.0057 (8) | 0.0084 (8) | 0.0045 (8) |
O3 | 0.0243 (11) | 0.0148 (10) | 0.0095 (9) | −0.0062 (9) | 0.0030 (8) | −0.0013 (8) |
O4 | 0.0142 (9) | 0.0105 (8) | 0.0085 (8) | −0.0014 (7) | 0.0043 (7) | 0.0010 (7) |
O5 | 0.0112 (8) | 0.0130 (9) | 0.0097 (8) | −0.0010 (7) | 0.0035 (7) | −0.0027 (7) |
O6 | 0.0100 (8) | 0.0163 (10) | 0.0137 (9) | −0.0035 (7) | 0.0024 (7) | 0.0018 (8) |
O7 | 0.0193 (11) | 0.0301 (13) | 0.0147 (10) | −0.0132 (10) | 0.0070 (9) | −0.0012 (9) |
Cd1—O7 | 2.235 (2) | Cd3—O6 | 2.330 (2) |
Cd1—O4i | 2.237 (2) | Cd3—O7iv | 2.478 (3) |
Cd1—O5 | 2.262 (2) | Cd3—O7v | 2.478 (3) |
Cd1—O1ii | 2.314 (2) | Cd3—O1vi | 2.860 (2) |
Cd1—O6i | 2.353 (2) | Cd3—O1vii | 2.860 (2) |
Cd1—O4 | 2.539 (2) | Te1—O2viii | 1.873 (2) |
Cd2—O4iii | 2.327 (2) | Te1—O5 | 1.882 (2) |
Cd2—O4 | 2.327 (2) | Te1—O6ix | 1.936 (2) |
Cd2—O5iii | 2.339 (2) | Te1—O2iii | 2.476 (2) |
Cd2—O5 | 2.339 (2) | Te2—O1 | 1.859 (2) |
Cd2—O2iii | 2.395 (2) | Te2—O4 | 1.890 (2) |
Cd2—O2 | 2.395 (2) | Te2—O3 | 1.928 (2) |
Cd2—O3 | 2.809 (2) | Te2—O6 | 2.441 (2) |
Cd2—O3iii | 2.809 (2) | Te3—O7v | 1.876 (2) |
Cd3—O1iii | 2.318 (2) | Te3—O7iv | 1.876 (2) |
Cd3—O1 | 2.318 (2) | Te3—O3vi | 2.088 (2) |
Cd3—O6iii | 2.330 (2) | Te3—O3vii | 2.088 (2) |
O7—Cd1—O5 | 89.60 (8) | O2viii—Te1—O5 | 98.70 (9) |
O4i—Cd1—O5 | 132.70 (7) | O2viii—Te1—O6ix | 91.48 (10) |
O7—Cd1—O1ii | 82.92 (9) | O5—Te1—O6ix | 92.74 (9) |
O4i—Cd1—O1ii | 90.83 (8) | O2viii—Te1—O2iii | 76.42 (10) |
O5—Cd1—O1ii | 122.23 (8) | O5—Te1—O2iii | 80.70 (8) |
O7—Cd1—O6i | 147.00 (9) | O6ix—Te1—O2iii | 165.07 (9) |
O4i—Cd1—O6i | 75.74 (7) | O1—Te2—O4 | 108.01 (10) |
O5—Cd1—O6i | 80.31 (7) | O1—Te2—O3 | 89.85 (10) |
O1ii—Cd1—O6i | 76.40 (8) | O4—Te2—O3 | 86.37 (9) |
O7—Cd1—O4 | 92.99 (8) | O1—Te2—O6 | 75.66 (9) |
O4i—Cd1—O4 | 75.55 (8) | O4—Te2—O6 | 80.14 (8) |
O5—Cd1—O4 | 78.97 (7) | O3—Te2—O6 | 155.89 (9) |
O1ii—Cd1—O4 | 158.20 (7) | O7v—Te3—O7iv | 92.57 (17) |
O6i—Cd1—O4 | 115.38 (7) | O7v—Te3—O3vi | 92.56 (10) |
O4iii—Cd2—O4 | 91.55 (10) | O7iv—Te3—O3vi | 86.72 (9) |
O4iii—Cd2—O5iii | 81.98 (7) | O7v—Te3—O3vii | 86.72 (9) |
O4—Cd2—O5iii | 162.69 (7) | O7iv—Te3—O3vii | 92.56 (10) |
O4iii—Cd2—O5 | 162.69 (7) | O3vi—Te3—O3vii | 178.97 (13) |
O4—Cd2—O5 | 81.98 (7) | O7—Cd1—O4i | 130.55 (8) |
O5iii—Cd2—O5 | 108.48 (10) | Te2—O1—Cd1x | 123.87 (11) |
O4iii—Cd2—O2iii | 95.61 (7) | Te2—O1—Cd3 | 116.49 (11) |
O4—Cd2—O2iii | 120.19 (7) | Cd1x—O1—Cd3 | 104.08 (9) |
O5iii—Cd2—O2iii | 76.60 (7) | Te1xi—O2—Cd2 | 115.99 (10) |
O5—Cd2—O2iii | 74.25 (7) | Te1xi—O2—Te1iii | 103.58 (10) |
O4iii—Cd2—O2 | 120.19 (7) | Cd2—O2—Te1iii | 90.75 (7) |
O4—Cd2—O2 | 95.61 (7) | Te2—O3—Te3vii | 126.44 (11) |
O5iii—Cd2—O2 | 74.24 (7) | Te2—O4—Cd1i | 112.50 (10) |
O5—Cd2—O2 | 76.60 (7) | Te2—O4—Cd2 | 113.86 (9) |
O2iii—Cd2—O2 | 128.99 (11) | Cd1i—O4—Cd2 | 118.33 (9) |
O1iii—Cd3—O1 | 90.65 (12) | Te2—O4—Cd1 | 113.10 (9) |
O1iii—Cd3—O6iii | 70.32 (8) | Cd1i—O4—Cd1 | 104.45 (8) |
O1—Cd3—O6iii | 76.77 (8) | Cd2—O4—Cd1 | 92.39 (7) |
O1iii—Cd3—O6 | 76.77 (8) | Te1—O5—Cd1 | 120.92 (10) |
O1—Cd3—O6 | 70.32 (8) | Te1—O5—Cd2 | 109.97 (9) |
O6iii—Cd3—O6 | 132.57 (11) | Cd1—O5—Cd2 | 99.61 (8) |
O1iii—Cd3—O7iv | 138.48 (8) | Te1iv—O6—Cd3 | 126.44 (11) |
O1—Cd3—O7iv | 115.36 (8) | Te1iv—O6—Cd1i | 113.29 (9) |
O6iii—Cd3—O7iv | 143.97 (8) | Cd3—O6—Cd1i | 102.51 (8) |
O6—Cd3—O7iv | 82.22 (8) | Te1iv—O6—Te2 | 119.89 (10) |
O1iii—Cd3—O7v | 115.35 (8) | Cd3—O6—Te2 | 96.53 (7) |
O1—Cd3—O7v | 138.48 (8) | Cd1i—O6—Te2 | 91.58 (8) |
O6iii—Cd3—O7v | 82.22 (8) | Te3xii—O7—Cd1 | 121.22 (12) |
O6—Cd3—O7v | 143.97 (8) | Te3xii—O7—Cd3xii | 100.54 (11) |
O7iv—Cd3—O7v | 66.35 (10) | Cd1—O7—Cd3xii | 99.69 (10) |
Symmetry codes: (i) −x+1/2, −y+1/2, −z+1; (ii) x+1/2, −y+1/2, z+1/2; (iii) −x, y, −z+1/2; (iv) −x+1/2, y+1/2, −z+1/2; (v) x−1/2, y+1/2, z; (vi) x, −y+1, z+1/2; (vii) −x, −y+1, −z; (viii) x, −y, z−1/2; (ix) −x+1/2, y−1/2, −z+1/2; (x) x−1/2, −y+1/2, z−1/2; (xi) x, −y, z+1/2; (xii) x+1/2, y−1/2, z. |
Cd5(TeO3)4(NO3)2 | F(000) = 1212 |
Mr = 1388.42 | Dx = 5.094 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 9.9442 (4) Å | Cell parameters from 3799 reflections |
b = 5.6173 (2) Å | θ = 2.5–36.2° |
c = 16.6136 (7) Å | µ = 12.19 mm−1 |
β = 102.737 (1)° | T = 300 K |
V = 905.19 (6) Å3 | Plate, colorless |
Z = 2 | 0.08 × 0.03 × 0.02 mm |
Bruker APEXII CCD diffractometer | 3381 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.050 |
ω– and φ–scan | θmax = 36.3°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | h = −16→16 |
Tmin = 0.517, Tmax = 0.747 | k = −9→9 |
17368 measured reflections | l = −27→27 |
4388 independent reflections |
Refinement on F2 | 133 parameters |
Least-squares matrix: full | 0 restraints |
R[F2 > 2σ(F2)] = 0.030 | w = 1/[σ2(Fo2) + (0.0232P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.061 | (Δ/σ)max = 0.001 |
S = 0.99 | Δρmax = 1.56 e Å−3 |
4388 reflections | Δρmin = −2.37 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Cd1 | 0.00202 (3) | 0.42718 (5) | 0.15555 (2) | 0.01465 (6) | |
Cd2 | 0.21172 (3) | 0.44982 (4) | 0.36945 (2) | 0.01363 (6) | |
Cd3 | 0.000000 | 0.000000 | 0.000000 | 0.01447 (8) | |
Te1 | 0.25779 (3) | 0.52156 (4) | 0.01753 (2) | 0.01033 (5) | |
Te2 | 0.78086 (3) | 0.41573 (4) | 0.28168 (2) | 0.01047 (5) | |
N1 | 0.4949 (5) | 0.0392 (8) | 0.0997 (2) | 0.0293 (9) | |
O1 | 0.0761 (3) | 0.0414 (5) | 0.13841 (16) | 0.0160 (6) | |
O2 | 0.1195 (3) | 0.6723 (5) | 0.25746 (15) | 0.0127 (5) | |
O3 | 0.1359 (3) | 0.2104 (4) | 0.46235 (16) | 0.0137 (5) | |
O4 | 0.1855 (3) | 0.1145 (5) | 0.30190 (18) | 0.0203 (6) | |
O5 | 0.1876 (3) | 0.5679 (5) | 0.11038 (17) | 0.0182 (6) | |
O6 | 0.3682 (4) | 0.0604 (8) | 0.0832 (3) | 0.0434 (10) | |
O7 | 0.4500 (5) | 0.3493 (8) | 0.4139 (3) | 0.0530 (12) | |
O8 | 0.5720 (5) | 0.2089 (9) | 0.1271 (3) | 0.0551 (12) | |
O9 | 0.8429 (3) | 0.2369 (4) | 0.04836 (16) | 0.0138 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.01571 (14) | 0.01295 (11) | 0.01570 (12) | −0.00266 (10) | 0.00435 (10) | −0.00525 (9) |
Cd2 | 0.02103 (15) | 0.00881 (10) | 0.01172 (11) | 0.00022 (10) | 0.00505 (10) | 0.00000 (8) |
Cd3 | 0.0210 (2) | 0.01277 (15) | 0.01182 (16) | −0.00376 (15) | 0.00839 (15) | −0.00284 (13) |
Te1 | 0.01106 (11) | 0.00940 (9) | 0.01050 (10) | 0.00022 (8) | 0.00232 (8) | −0.00003 (7) |
Te2 | 0.01209 (12) | 0.00921 (9) | 0.01048 (10) | 0.00040 (8) | 0.00330 (8) | −0.00012 (7) |
N1 | 0.022 (2) | 0.042 (2) | 0.0236 (19) | −0.0042 (19) | 0.0051 (16) | 0.0085 (17) |
O1 | 0.0220 (16) | 0.0136 (12) | 0.0116 (12) | 0.0061 (11) | 0.0021 (11) | 0.0020 (9) |
O2 | 0.0152 (14) | 0.0128 (11) | 0.0100 (11) | −0.0037 (10) | 0.0027 (10) | 0.0012 (9) |
O3 | 0.0166 (15) | 0.0095 (11) | 0.0152 (12) | 0.0043 (10) | 0.0041 (11) | 0.0038 (9) |
O4 | 0.0251 (17) | 0.0159 (13) | 0.0214 (14) | −0.0027 (12) | 0.0088 (12) | −0.0089 (11) |
O5 | 0.0222 (16) | 0.0200 (13) | 0.0141 (12) | −0.0042 (12) | 0.0076 (12) | −0.0041 (10) |
O6 | 0.0172 (19) | 0.059 (3) | 0.054 (2) | 0.0039 (18) | 0.0081 (17) | 0.024 (2) |
O7 | 0.041 (3) | 0.039 (2) | 0.075 (3) | −0.010 (2) | 0.003 (2) | −0.001 (2) |
O8 | 0.036 (3) | 0.065 (3) | 0.058 (3) | −0.014 (2) | −0.003 (2) | −0.016 (2) |
O9 | 0.0165 (15) | 0.0084 (11) | 0.0158 (12) | 0.0016 (10) | 0.0023 (11) | 0.0006 (9) |
Cd1—O5 | 2.281 (3) | Cd3—O1v | 2.269 (3) |
Cd1—O2 | 2.292 (3) | Cd3—O3vi | 2.289 (3) |
Cd1—O1 | 2.326 (3) | Cd3—O3iii | 2.289 (3) |
Cd1—O9i | 2.361 (3) | Cd3—O9vii | 2.326 (3) |
Cd1—O4ii | 2.380 (3) | Cd3—O9i | 2.326 (3) |
Cd1—O2iii | 2.524 (3) | Te1—O5 | 1.847 (3) |
Cd1—O3ii | 2.658 (3) | Te1—O3vi | 1.875 (3) |
Cd2—O4 | 2.179 (3) | Te1—O9viii | 1.886 (3) |
Cd2—O9iv | 2.256 (3) | Te2—O1iv | 1.858 (3) |
Cd2—O2 | 2.261 (3) | Te2—O4iv | 1.869 (3) |
Cd2—O3 | 2.296 (3) | Te2—O2ix | 1.886 (3) |
Cd2—O7 | 2.389 (5) | N1—O6 | 1.234 (5) |
Cd2—O8iv | 2.587 (5) | N1—O7ix | 1.242 (6) |
Cd3—O1 | 2.269 (3) | N1—O8 | 1.245 (6) |
O5—Cd1—O2 | 73.58 (9) | O3iii—Cd3—O9vii | 99.77 (9) |
O5—Cd1—O1 | 88.94 (10) | O1—Cd3—O9i | 71.97 (10) |
O2—Cd1—O1 | 121.76 (10) | O1v—Cd3—O9i | 108.03 (10) |
O5—Cd1—O9i | 111.40 (10) | O3vi—Cd3—O9i | 99.77 (9) |
O2—Cd1—O9i | 167.59 (10) | O3iii—Cd3—O9i | 80.23 (9) |
O1—Cd1—O9i | 70.34 (10) | O9vii—Cd3—O9i | 180.00 (16) |
O5—Cd1—O4ii | 133.48 (10) | O5—Te1—O3vi | 100.59 (12) |
O2—Cd1—O4ii | 79.64 (10) | O5—Te1—O9viii | 97.66 (12) |
O1—Cd1—O4ii | 137.57 (10) | O3vi—Te1—O9viii | 90.73 (12) |
O9i—Cd1—O4ii | 89.17 (10) | O1iv—Te2—O4iv | 93.99 (13) |
O5—Cd1—O2iii | 155.39 (10) | O1iv—Te2—O2ix | 98.29 (12) |
O2—Cd1—O2iii | 98.53 (6) | O4iv—Te2—O2ix | 89.04 (12) |
O1—Cd1—O2iii | 75.29 (9) | Te2ix—O1—Cd3 | 135.81 (14) |
O9i—Cd1—O2iii | 81.33 (9) | Te2ix—O1—Cd1 | 118.66 (13) |
O4ii—Cd1—O2iii | 64.87 (9) | Cd3—O1—Cd1 | 100.13 (10) |
O4—Cd2—O9iv | 155.85 (11) | Te2iv—O2—Cd2 | 122.40 (13) |
O4—Cd2—O2 | 94.20 (10) | Te2iv—O2—Cd1 | 113.69 (11) |
O9iv—Cd2—O2 | 89.70 (9) | Cd2—O2—Cd1 | 108.91 (11) |
O4—Cd2—O3 | 79.63 (10) | Te2iv—O2—Cd1ii | 98.06 (11) |
O9iv—Cd2—O3 | 81.57 (9) | Cd2—O2—Cd1ii | 90.05 (8) |
O2—Cd2—O3 | 138.01 (10) | Cd1—O2—Cd1ii | 122.22 (12) |
O4—Cd2—O7 | 87.31 (14) | Te1x—O3—Cd3ii | 135.82 (13) |
O9iv—Cd2—O7 | 109.67 (13) | Te1x—O3—Cd2 | 117.59 (13) |
O2—Cd2—O7 | 125.43 (13) | Cd3ii—O3—Cd2 | 93.93 (9) |
O3—Cd2—O7 | 95.97 (13) | Te2ix—O4—Cd2 | 151.47 (17) |
O4—Cd2—O8iv | 120.16 (14) | Te2ix—O4—Cd1iii | 103.71 (13) |
O9iv—Cd2—O8iv | 83.95 (13) | Cd2—O4—Cd1iii | 104.00 (11) |
O2—Cd2—O8iv | 83.78 (12) | Te1—O5—Cd1 | 135.10 (15) |
O3—Cd2—O8iv | 135.16 (12) | N1iv—O7—Cd2 | 100.8 (3) |
O7—Cd2—O8iv | 50.43 (14) | N1—O8—Cd2ix | 91.1 (3) |
O1—Cd3—O1v | 180.0 | Te1viii—O9—Cd2ix | 134.23 (15) |
O1—Cd3—O3vi | 96.84 (10) | Te1viii—O9—Cd3xi | 121.47 (12) |
O1v—Cd3—O3vi | 83.16 (10) | Cd2ix—O9—Cd3xi | 94.00 (9) |
O1—Cd3—O3iii | 83.16 (10) | Te1viii—O9—Cd1xi | 107.10 (11) |
O1v—Cd3—O3iii | 96.84 (10) | Cd2ix—O9—Cd1xi | 94.47 (9) |
O3vi—Cd3—O3iii | 180.00 (15) | Cd3xi—O9—Cd1xi | 97.48 (10) |
O1—Cd3—O9vii | 108.03 (10) | O6—N1—O7ix | 120.8 (5) |
O1v—Cd3—O9vii | 71.97 (10) | O6—N1—O8 | 121.6 (5) |
O3vi—Cd3—O9vii | 80.23 (9) | O7ix—N1—O8 | 117.6 (5) |
Symmetry codes: (i) x−1, y, z; (ii) −x, y+1/2, −z+1/2; (iii) −x, y−1/2, −z+1/2; (iv) −x+1, y+1/2, −z+1/2; (v) −x, −y, −z; (vi) x, −y+1/2, z−1/2; (vii) −x+1, −y, −z; (viii) −x+1, −y+1, −z; (ix) −x+1, y−1/2, −z+1/2; (x) x, −y+1/2, z+1/2; (xi) x+1, y, z. |
Footnotes
‡Present address: Department of Quantum Matter Physics, Ecole de Physique, University of Geneva, 24, Quai Ernest-Ansermet, CH – 1211 Geneva 4, Switzerland.
Acknowledgements
The X-ray centre of the TU Wien is acknowledged for providing access to the single-crystal and powder X-ray diffractometers. We thank TU Wien Bibliothek for financial support through its Open Access Funding Programme.
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