Tetrahedral Coordination Research Articles

DFT insights into hydrogen activation on the doping Ni2P surfaces under the hydrodesulfurization condition

Hydrogen activation on the different Ni2P surfaces were explored under the traditional hydrodesulfurization conditions using density function theory (DFT) calculations. Firstly, the H2 dissociative adsorption phase diagrams were calculated and compared on the Ni(I)- and Ni(II)-exposed surfaces. The H2 dissociative adsorption on the Ni(I)-exposed surface had high activity below 4 H2 coverage, and the H2 dissociative adsorption on the Ni(II)-exposed surface was preferable below 2 H2 coverage. By contrast, the Ni(I)-exposed surface exhibited higher H2 activation activity than that on the Ni(II)-exposed surface. Moreover, the dissociative H atoms on Ni(II)-exposed surface would lead the rearrangement of surface Ni atoms to form the quasi tetrahedral coordination structure, which was similar to that of Ni(I)-exposed surface. Secondly, the surface phase diagrams were discussed on the different transition metals (Cr, Fe, Co, Cu or Mo) doping Ni(I)-exposed surfaces. The results revealed that H2 activation ability followed the order: Fe > Co > Mo > Cr > Ni > Cu. Furthermore, the difference charge densities and bader charge analysis were calculated to provide the additional information for understanding the phenomenon clearly, and the results indicated that the difficulty sequence of charge transfer between transition metals atom and H atoms was completely consistent with the above research.

Catalytic production of γ-valerolactone from xylose over delaminated Zr-Al-SCM-1 zeolite via a cascade process

A series of delaminated MWW-type Zr-Al-SCM-1 zeolites with large external surface area have been synthesized through a post-synthesized method by partial dealumination of SCM-1 and Zr incorporation based on parent SCM-1 zeolite, and used in the conversion of furfural and xylose to γ-valerolactone (GVL). The characterization of catalysts using XRD, FTIR, 29Si NMR, Raman, UV–vis and XPS spectroscopy confirmed the preservation of the parent SCM-1 zeolite network as well as the incorporation of Zr atoms into the zeolite framework with tetrahedral coordination. NH3-TPD and Py-FTIR spectroscopy reveal that the Zr-Al-SCM-1 zeolites possess both Brønsted and Lewis acid sites. When they are applied to the one-pot cascade conversion of furfural, a remarkable GVL yield of 47.3% with 85.6% carbon balance is obtained at 170 °C after 28 h. When considering xylose as starting substrate, up to 36.4% yield of GVL is achieved over Zr-Al-SCM-1 zeolites with excellent recyclability at 170 °C after 48 h. Moreover, the catalyst shows far superior catalytic performance and stability compared to the commercial MCM-22 based zeolites (Zr-Al-MCM-22).

Propiedades fisicoquímicas de V/Ti-PILC: efecto del contenido de V en la oxidación selectiva del alcohol bencílico

Las arcillas minerales son atractivas como catalizadores debido a su bajo costo y alta disponibilidad. En este sentido se sintetizaron Ti-PILCs, las cuales fueron posteriormente modificadas con distintos contenidos de vanadio (0,1; 0,5 y 1% en peso). Todos los materiales pilareados presentaron espaciamiento basal y área específica superiores respecto a la arcilla original (Na-mont), lo que permitió una buena dispersión de las especies de V incorporadas.Los catalizadores V/Ti-PILC mostraron una mayor conversión de alcohol bencílico (BzOH) que Ti-PILC, que mejoró al aumentar la carga de vanadio hasta 0,5 % en peso, alcanzando un valor de 42,82 % mol a las 5 h de reacción. Este hecho podría atribuirse a la presencia de iones V aislados en coordinación tetraédrica, altamente dispersos. En cambio, la disminución en la conversión de BzOH con V(1%)/Ti-PILC, estaría asociado tanto a la presencia de especies de V polimérico (observado por UV-vis-RD) como a la disminución del área específica debido al bloqueo de los poros por las especies de V. Para el catalizador más activo, V(0,5%)/Ti PILC, la selectividad a benzaldehído (BzH) alcanzó un valor de 94,72% mol luego de 5 h de reacción.

Atom-planting synthesis of MCM-36 catalyst to investigate the influence of pore structure and titanium coordination state on epoxidation activity

Abstract The borosilicate ERB-1 was modified as titanosilicate with microporous and mesoporous composite MCM-36 structure accommodated as epoxidation catalyst for large size molecule of reactants in the aqueous solution. Ti-MCM-36 was synthesized by swelling and pillaring the MWW layer structure with SiO2 and atom-planting method with TiCl4. The 2D 1H double quantum NMR and in-situ infrared spectroscopy confirm that the swelling process with cetyltrimethylammonium bromide and tetrapropylammonium hydroxide for the MCM-36 synthesis causes the deboronation of the ERB-1 and formation of hydroxyl nest. During the atom-planting treatment, the TiCl4 reacts with the generated hydroxyl group and consumes the hydroxyl nest to form the tetrahedral titanium in the zeolite framework as Ti–O–Si. The UV–Vis spectra show that the incorporated titanium atoms are mainly existed in the form of tetracoordinated titanium. The titanosilicate pillared Si/Ti-MCM-36 with coexistence of tetrahedral and octahedral coordination titanium species were compared with Ti-MCM-36 to investigate the coordination state of Ti species for the liquid phase epoxidation of cyclohexene, cyclooctene with tert-butyl hydroperoxide aqueous solution, decane solution or H2O2 solution. Moreover, compared with the extra-framework octahedral coordination Ti species, the framework tetrahedral coordination titanium species are more efficient for epoxidation, especially with H2O2 as oxidant. By comparing with the performance of microporous Ti-ERB-1, the microporous and mesoporous composite Ti-MCM-36 is more efficient with the increase of the reactant molecule size from 1-hexene, cyclohexene, cyclooctene and soybean oil, which shows good epoxidation activity for soybean oil within H2O2 solution.

Cover Feature: A Phosphine Functionalized β‐Diketimine Ligand for the Synthesis of Manifold Metal Complexes (Chem. Eur. J. 58/2020)

A bis(diphenyl)-phosphine functionalized β-diketimine ligand is depicted in the cover image. This ligand coordinates in a very flexible manner to a number of transition metal ions. The newly designed ligand features a symmetrically placed PNNP-type pocket. Due to the hard and soft donor atoms (N vs. P) the ligand can stabilize various coordination polyhedra. A complete series ranging from coordination numbers 2 to 6 was realized, resulting in linear, trigonal planar, square planar, tetrahedral, square pyramidal, and octahedral coordination polyhedral. More information can be found in the Full Paper by P. W. Roesky et al. on page 13191.

Iron carbonyl complexes of a rigid chelating dicarbene: A density functional theory study

The series of vegiR dicarbenes with a phenanthroline-like backbone synthesized by Kunz and co-workers provide rigid chelating bidentate ligands with carbon donor atoms. Such ligands can, in principle, replace two carbonyl groups in a metal carbonyl derivative leading to analogues of metal carbonyls but with weaker-field carbon-based ligands. Density functional theory has been used to investigate the structures and energetics of the iron carbonyl complexes (vegiMe)Fe(CO)n (n = 3, 2) and (vegiMe)Fe2(CO)n (n = 7, 6, 5) of the simplest such ligands with methyl substituents. Replacement of two carbonyl groups in Fe(CO)5 with one vegiMe ligand is predicted to give trigonal bipyramidal and tetragonal pyramidal isomers of the tricarbonyl (vegiMe)Fe(CO)3 having similar energies within ~2 kcal/mol suggesting a fluxional system. Removal of a carbonyl group from (vegiMe)Fe(CO)3 is predicted to give singlet and triplet (vegiMe)Fe(CO)2 dicarbonyl structures with similar energies having a hole in the coordination sphere for the “missing” carbonyl group. A quintet (vegiMe)Fe(CO)2 structure with tetrahedral FeC4 coordination is a higher energy isomer by ~10 kcal/mol. The three lowest energy (vegiMe)Fe2(CO)7 structures, obtained by replacing two carbonyl groups in Fe2(CO)9 with one vegiMe ligand, have the vegiMe ligand bridging a Fe–Fe single bond to form a six-membered Fe2CN2C ring. Isomeric (vegiMe)Fe2(CO)7 structures with the vegiMe ligand chelated to a single iron atom forming a five-membered FeC2N2 ring lie at least 10 kcal/mol above the lowest energy isomer. The lowest energy isomers of the unsaturated (vegiMe)Fe2(CO)n (n = 6, 5) are triplet and quintet spin state structures reflecting the lower field strength of the vegiR ligands relative to carbonyl groups.

Tetra-kis(di-cyclo-hexyl-amido)-zirconium(IV).

The reaction of ZrCl4 with three equivalents of LiNCy2 (Cy is cyclo-hex-yl) resulted in the formation of tris-(di-cyclo-hexyl-amido)-zirconium chloride and the title compound, [Zr(C12H22N)4]. The latter is isotypic with its cerium(IV) analogue and crystallizes with three independent mol-ecules in the asymmetric unit. One mol-ecule is located about a twofold rotation axis, and the other two on fourfold inversion axes. In each mol-ecule, the ZrIV atom has a distorted tetra-hedral coordination environment. The crystal under investigation was twinned by inversion in a 1:1 ratio.

Tetrahedral copper(I) complexes of novel N,N-bidentate ligands and photophysical properties

A series of copper(I) complexes [Cu(L)(PPh3)2]NO3 (1–5) of bidentate ligands 2-pyridin-2-yl-quinoline (L1), 4-phenyl-2-pyridin-2-yl-quinoline (L2) 2-pyridin-2-yl-quinoxaline (L3), 6,7-dimethyl-2-(pyridin-2-yl)quinoxaline (L4), and 4-phenyl-2-pyridin-2-yl-quinazoline (L5) have been synthesized and characterized by elemental analysis, absorption, emission, IR, 1H, 13C, 31P NMR spectroscopies and redox method. Of these complexes [Cu(L1)(PPh3)2]NO3 (1), [Cu(L3)(PPh3)2]NO3 (3), and [Cu(L4)(PPh3)2]NO3 (4) are structurally characterized by single-crystal X-ray analysis. They exhibited distorted tetrahedral coordination geometries around the copper(I) center with τ4 values of 0.77–0.86. In the solid-state, all these complexes have exhibited emission in the range of 450–750 nm and their excited-state lifetimes were measured as of 1.9–8.9 μs. However, all the complexes were found to be weak emissive in solution due to the excited state structural rearrangement. Further, Time-dependent density-functional theory (TDDFT) calculations showed that the charge transfers are mainly caused by the contribution of HOMO-2 → LUMO, HOMO-1 → LUMO and HOMO → LUMO orbitals.

Vanadium-induced coloration in grossite (CaAl4O7) and hibonite (CaAl12O19)

AbstractHigh concentrations of vanadium cause very unusual coloration in hibonite (purple) and grossite (light violet) crystals in an exotic mineral assemblage from Sierra de Comechingones (Argentina). In the hibonite (CaAl12O19) structure vanadium ions, in various valence states (divalent, trivalent, and tetravalent), may be distributed over five crystallographic sites with coordinations corresponding to different polyhedra, namely, three unequal octahedra [M1 (D3d), M4 (C3ν), and M5 (Cs)], one M3 tetrahedron (C3ν), and one unusual fivefold-coordinated trigonal bipyramid M2 (D3h). Possible locations of vanadium ions in grossite (CaAl4O7) are limited to two crystallographically distinct sites (T1 and T2, both C1) in tetrahedral coordination.The combination of single-crystal X-ray diffraction and absorption spectroscopy techniques aided by chemical analyses has yielded details on the nature of the vanadium-induced color in both hibonite and grossite crystals. In hibonite, both M4 face-sharing octahedral and M2 trigonal bipyramid sites of the R-block are partially occupied by V3+. Strongly polarized bands recorded at relatively low energies in optical absorption spectra indicate that V2+ is located at the M4 octahedral site of the hibonite R-block. Chemical analyses coupled with an accurate determination of the electron densities at structural sites in hibonite suggest that the vanadium ions occupy about 10 and 5% of the M4 and M2 sites, respectively. For grossite, polarized optical absorption spectra reveal no indications of V2+; all observed absorption bands can be assigned to V3+ in tetrahedral coordination. Although not evident by the observed electron densities at the T sites of grossite (due to the low-V content), longer bond distances, and a higher degree of polyhedral distortion suggest that V3+ is located at the T2 site.

Structural and Morphological Features of Polycrystalline Aluminum Oxide Surface after Nanocoating with Titanium Oxide of Different Thickness

Using the molecular layering method, titanium oxide coatings were synthesized on the surface of polycrystalline aluminum oxide plates by alternating treatment with titanium tetrachloride and water vapors. It was shown by means of diffuse reflection electron spectroscopy that at different nanocoating thickness, surface complexes differing in structure are formed: distorted octahedral (alumotitanate), those with tetrahedral titanium coordination, and polyhedra with anatase-like environment of the central atom. The surface morphology changes during the synthesis and after 600 layering cycles the titanium oxide coating covers the entire surface of the initial substrate.

Synthesis and Structure of Tetra(para-tolyl)antimony Dicyanodiiodoaurate [p-Tol4Sb][Au(CN)2I2] and Alkyltriphenylphosphonium Dicyanodiiodoaurates [Ph3PAlk][Au(CN)2I2], Alk = Me, CH2CN

Red-colored crystalline gold complexes [p-Tol4Sb][Au(CN)2I2] (I), [Ph3PMe][Au(CN)2I2] (II), and [Ph3PCH2CN][Au(CN)2I2] (III) were synthesized by the reaction of potassium dicyanodiiodoaurate with tetra(para-tolyl)antimony and alkyltriphenylphosphonium halides in water. The structure of the complexes was established by IR and NMR spectroscopy and X-ray diffraction. The tetra(para-tolyl)antimony and alkyltriphenylphosphonium cations have a distorted tetrahedral coordination. The dicyanodiiodoaurate anions have a planar structure with a square coordination of the gold atom. The formation of the 3D crystal network is due to weak CN⋅⋅⋅H−C hydrogen bonds between cations and anions (2.39, 2.59 A (I), 2.70, 2.48, 2.52, 2.68 A (II), 2.73, 2.50, 2.67, 2.44 A (III)). In complex III, anions of one of the two types interact with one another via I⋅⋅⋅I contacts to give 1D ladder-like chains along the crystallographic a axis.

Luminescent Dinuclear Copper(I) Complexes Bearing an Imidazolylpyrimidine Bridging Ligand.

The synthesis and photophysical study of two dinuclear copper(I) complexes bearing a 2-(1H-imidazol-2-yl)pyrimidine bridging ligand are described. The tetrahedral coordination sphere of each copper center is completed through the use of a bulky bis(phosphine) ligand, either DPEphos or Xantphos. Temperature-dependent photophysical studies demonstrated emission through a combination of phosphorescence and thermally activated delayed fluorescence for both complexes, and an intense emission (ΦPL = 46%) was observed for a crystalline sample of one of the complexes reported. The photophysics of these two complexes is very sensitive to the environment. Two pseudopolymorphs of one of the dinuclear complexes were isolated, with distinct photophysics. The emission color of the crystals can be changed by grinding, and the differences in their photophysics before and after grinding are discussed.

A Phosphine Functionalized β-Diketimine Ligand for the Synthesis of Manifold Metal Complexes.

A bis(diphenyl)‐phosphine functionalized β‐diketimine (PNac‐H) was synthesized as a flexible ligand for transition metal complexes. The newly designed ligand features symmetrically placed phosphine moieties around a β‐diketimine unit, forming a PNNP‐type pocket. Due to the hard and soft donor atoms (N vs. P) the ligand can stabilize various coordination polyhedra. A complete series ranging from coordination numbers 2 to 6 was realized. Linear, trigonal planar, square planar, tetrahedral, square pyramidal, and octahedral coordination arrangements containing the PNac‐ligand around the metal center were observed by using suitable metal sources. Hereby, PNac‐H or its anion PNac− acts as mono‐, bi‐ and tetradendate ligand. Such a broad flexibility is unusual for a rigid tetradentate system. The structural motifs were realized by treatment of PNac‐H with a series of late transition metal precursors, for example, silver, gold, nickel, copper, platinum, and rhodium. The new complexes have been fully characterized by single crystal X‐ray diffraction, NMR, IR, UV/Vis spectroscopy, mass spectrometry as well as elemental analysis. Additionally, selected complexes were investigated regarding their photophysical properties. Thus, PNac‐H proved to be an ideal ligand platform for the selective coordination and stabilization of various metal ions in diverse polyhedra and oxidation states.

Evidence of Octahedral Co–Mo–S Sites in Hydrodesulfurization Catalysts as Determined by Resonant Inelastic X-ray Scattering and X-ray Absorption Spectroscopy

Fundamental understanding of the active sites in CoMo/Al2O3 catalysts is crucial to improve the production of clean transportation fuels by hydrodesulfurization (HDS). In this work, the coordination state and number of active sites (“Co–Mo–S”) in sulfided CoMo/Al2O3 catalysts prepared with and without chelating additives were determined using in situ 1s2p resonant inelastic X-ray scattering (RIXS) and X-ray absorption spectroscopy (XAS). Based on the evaluation of thiophene HDS activity as a function of the Co/Mo ratio, it was determined that only for Co/Mo < 0.1, cobalt is exclusively in interaction with the MoS2 phase, making these compositions ideal for identifying the nature of the active cobalt sites for hydrogenolysis. These cobalt promoter atoms were in centrosymmetric coordination with the MoS2 phase, with six sulfur ligands coordinated to each cobalt center. The octahedral coordination of cobalt in Co–Mo–S in alumina-supported HDS catalysts contrasts the tetrahedral cobalt coordination found in Co-promoted MoS2 model systems supported on gold or carbon. We attribute the difference to more disordered MoS2 structures in technical alumina-supported HDS catalysts. The number of Co–Mo–S sites depended strongly on the catalyst preparation method. Chelating additives, such as citric acid and nitrilotriacetic acid, increased the number of Co–Mo–S sites without significantly altering their intrinsic activity. These results demonstrate that the state-of-the-art structural characterization tools, such as RIXS, identify the structure of active sites in actual catalysts and that these structures may be different from model systems. Combining such characterization tools with guided catalyst design can provide an insight into the structure of amorphous, nanostructured materials, which aid in the development of improved heterogeneous catalysts. KEYWORDS:Hydrodesulfurization Co−Mo−S RIXS active site XAS

First principles study of the electronic, elastic, infrared and electrical properties of LiZnPS4

LiZnPS4 is thought to be a promising mid-infrared optical crystal and lithium battery material, but its fundamental properties are still not well investigated. In this work, we performed a systematic study on its electronic, elastic, infrared and electrical properties. The results indicate that LiZnPS4 is an indirect band gap crystal. Calculated partial density of states reveals that the top of its valence band is formed by the S 3p orbital while the component of the bottom of the conduction band is complex. The Zn 4p orbital is not empty in LiZnPS4 owing to the tetrahedral coordination of the Zn atoms. Calculated elastic properties indicate that LiZnPS4 is a mechanically stable crystal with elastic anisotropy. It has a relatively low Debye temperature of 294.8 K. Its infrared absorption spectrum was simulated and the origins of the strong peaks in it were revealed. Vibrational modes at the Brillouin zone center were illustrated and Born effective charges were calculated and discussed. Computed dielectric constants uncover that electrons contribute more to the total dielectric constants than ions. Studies imply that LiZnPS4–Li+ battery has a high theoretical voltage, a low electric capacity and a slightly high activation barrier.

Triplet grain growth in a-texture polycrystalline ZnO thin films

A growth of grain triplets is identified in vapor deposited, a-texture polycrystalline zinc oxide thin films, using a combination of transmission electron microscopy-based automated crystal orientation mapping and high-resolution imaging. Each triplet consists of three wurtzite phase grains, coordinated to near tetrahedral relative growth angles by the close-packed planes of a few nanometer diameter core of metastable zinc blende phase ZnO located at their triple junction. The triplets are aligned such that two of the grains have their fast growing [21¯1¯0] axes (near-) parallel to the substrate normal, and so coarsen under the principle of competitive grain growth. In contrast, growth of the third grain with a (101¯3) texture is impeded, such that it forms a small wedge between the ends of its two larger neighbors. Remarkably, all three boundaries between the grains adhere to a [21¯1¯0]/(011¯3) coherent twin orientation relationship, which corresponds to a grain geometry that is incommensurate with a perfect crystallographic nature. This coherency is primarily achieved via the small grain having an orientation that rotates internally by 10±2° across its volume, when going between the two interfaces formed with the neighboring large grains. The energy associated with this structural distortion is compensated by the formation of the coherent twin boundaries, such that the triplets are a stable or semi-stable growth form that are abundant in the film. The small (101¯3) texture grains may renucleate persistently, taking either of two possible orientations from the underlying tetrahedral coordination. By developing a phenomenological model for the triplet geometry and form, we associate these two orientations to small hexagonal caps and angled wedges seen in the surface morphology of the film. These findings potentially carry relevance for a wide range of vapor deposited compact films and free-standing nanostructures of wurtzite phase octet binary semiconductor compounds. We therefore believe that these insights can stimulate new research, for instance to obtain a more fundamental understanding of the growth mechanisms at the atomistic level.

The adsorption mechanism of Zn2+ by triclinic birnessite and the mechanism

ABSTRACT In this paper, the reaction mechanism for the adsorption of Zn2+ by synthetic triclinic Na-birnessite was studied by reacting synthetic triclinic Na-birnessite with Zn2+ in solution, thereby providing a theoretical basis for the purification of heavy metal ions in acid soil and water by triclinic birnessite. The adsorption effect of Zn2+ on Na-birnessite enhances with an increase in either reaction time or Na-birnessite dosage, as well as decrease of pH. Na-birnessite can effectively adsorb Zn2+ in acidic solutions without any secondary pollution, and the stronger the acidity, the better the treatment effect. In acidic conditions, H+ in solution exchanges with Na+ in the interlayer of triclinic Na-birnessite, then a small part of Zn2+ in solution exchanges with the Mn2+ produced during the triclinic-to-hexagonal phase transformation, and most of the Zn2+ forms a complex with OH− on the octahedral layer, which loses protons due to the consumption of H+ ions. Finally, Zn2+ adsorbs above and below octahedral vacancies in hexagonal birnessite in either an octahedral or tetrahedral coordination.

Competitive effect of dopant concentration and the size of the nanorods over the electron phonon coupling in Cd doped ZnO nanorod arrays

Earlier reports on resonance Raman scattering in ZnO suggests that the electron phonon coupling in ZnO usually increase with nanoparticle size or decline with the doping concentration. We investigated the effect of combination of the concentration of dopant and the variation of size of nanorods over the electron phonon interaction in Cd doped ZnO nanorod array fabricated by a simple, low temperature (90 °C) growth process. The resonant Raman measurement revealed minor decrease in the electron phonon coupling strength as defined by the intensity ratio (I2LO/I1LO) at low doping concentration (20 mol %) and increase at high Cd concentration (>20 mol %) confirming a strong dependence of electron phonon coupling strength on the concentration of dopant. The enhancement in the electron phonon coupling strength at high doping concentration was due to the increase in the diameter of the nanorod rather than the concentration of dopants explaining the competitive effect of dopant and size over the electron phonon interaction in a range of doping concentration. The Cd doping led to the decrease in the band gap and the increase (decrease) in the intensity of the excitonic emission (visible luminescence) as observed by the photoluminescence property. X-ray, Fourier transform infrared (FTIR) analysis confirmed low temperature doping of Cd at the tetrahedral coordination site of the ZnO lattice Although, the Cd concentration in the growth solution was systematically varied from 1 mol % to 80 mol %, the maximum Cd doping varied from 3 at. % (80 mol %) at the surface to 0.2 at % - 0.6 at. % in the bulk after surface cleaning by Ar ion etching.

Responsive Four-Coordinate Iron(II) Nodes in FePd(CN)4.

Metal node design is crucial for obtaining structurally diverse coordination polymers (CPs) and metal-organic frameworks with desirable properties; however, FeII ions are exclusively six-coordinated. Herein, we present a cyanide-bridged three-dimensional (3D) CP, FePd(CN)4 , bearing four-coordinate FeII ions, which is synthesized by thermal treatment of a two-dimensional (2D) six-coordinate FeII CP, Fe(H2 O)2 Pd(CN)4 ⋅4 H2 O, to remove water molecules. Atomic-resolution transmission electron microscopy and powder X-ray and neutron diffraction measurements revealed that the FePd(CN)4 structure is composed of a two-fold interpenetrated PtS topology network, where the FeII center demonstrates an intermediate geometry between tetrahedral and square-planar coordination. This four-coordinate FeII center with the distorted geometry can act as a thermo-responsive flexible node in the PtS network.

Das Ytterbium(III)-Oxidbromid-Oxidotellurat(IV) Yb3O2Br[TeO3]2

Abstract The ytterbium(III) oxide bromide oxidotellu-rate(IV) Yb3O2Br[TeO3]2 was obtained from a mixture of Yb2O3, YbBr3 and TeO2 in a molar ratio of 2:1:2 along with an excess of KBr as fluxing agent in evacuated fused silica ampoules after 10 days at T = 800 °C and subsequent slow cooling to room temperatures as colorless, plate-shaped single crystals. Its triclinic crystal structure (a = 663.97(5), b = 697.46(5), c = 1080.15(8) pm, α = 105.102(3), β = 90.931(3), γ = 100.034(3)°; Z = 2, space group: P 1 ‾ $&amp;#x203e;{1}$ ) displays three crystallographically different Yb3+ cations with coordination numbers of six, seven and eight. Six out of eight distinct oxygen atoms belong to two independent ψ1-tetrahedral [TeO3]2−anions, whereas the other two represent O2− anions in tetrahedral coordination of four Yb3+ cations each, not having any contact to tellurium. Condensed via common vertices and edges, these [OYb4]10+ tetrahedra form cationic layers ∞ 2 ${}_{\infty }{}^{2}$ {[O2Yb3]5+}, which spread out parallel to the (001) plane. Two discrete [TeO3]2− groups and one Br− anion per formula unit take care of their three-dimensional interconnection along [001] and the overall charge balance of Yb3O2Br[TeO3]2. Remarkable interactions between the lone pair of electrons at the Te4+ cations of the ψ1-tetrahedral [TeO3]2− anions and those at the Br− anions are discussed.