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Beryllium borates are mostly water-free, with the natural mineral berborite, Be 2 (BO 3)(OH)‧H 2 O, being the only known exception. A sample of berborite from the Vevja quarry, Tvedalen, Larvik, Norway was studied by single-crystal X-ray diffraction, variable temperature 1H nuclear magnetic resonance (NMR), and infrared (IR) spectroscopy. The crystal structure is the trigonal 1 T -polytype with space group P 321 and is based on electroneutral [BeØ 2 (BΔO 3)]-layers formed by BeO 3 Ø-tetrahedra and BΔO 3 -triangles. Due to statistical occupancy of the Ø-ligand by hydroxyl groups (50%) and water molecules (50%), berborite-1 T and its related polytypes are characterized by complex systems of hydrogen bonds. Accurate analysis shows that in the structure of berborite there are two independent systems of hydrogen bonds involving mobile protons. Lowering of temperature results in the complete stabilization of protons at the critical "freezing-point" of 243 K. The crystal chemistry and complexity of layered beryllium borates are discussed. Despite the broad structural diversity of these compounds, their crystal structures are classified as simple (20–100 bits per unit cell) or intermediately complex (100–500 bits per unit cell). The complexity of berborite polytypes increases in accordance with the quantity of layers from 29.038 (1 T) to 78.077 (2 H), which is in good agreement with the negative contribution of complexity to the configurational entropy. • A sample of was studied by SCXRD, variable temperature 1H NMR, and IR spectroscopy. • In the berborite structure there are two substantially independent systems of hydrogen bonds involving mobile protons. • The crystal chemistry and complexity of layered beryllium borates are discussed. [ABSTRACT FROM AUTHOR]

In the study of the Rb 2 MoO 4 –CoMoO 4 –Hf(MoO 4) 2 system a new compound, Rb 5 Hf 1.5 Сo 0.5 (MoO 4) 6 , was obtained, which was synthesized by ceramic technology at 530°С for 80 h in air. Rb 5 Hf 1.5 Сo 0.5 (MoO 4) 6 single crystals were grown by spontaneous crystallization from a melt solution. Synthesized molybdate melt incongruently at 670 °C. The crystal structure has been refined using single-crystal X-ray diffraction data. Triple molybdate Rb 5 Hf 1.5 Сo 0.5 (MoO 4) 6 (a = 10.6169(4) Å, c = 38.1282(5) Å. V = 3722.02(2) Å3; space group R 3 ‾ c , Z = 6) is characterized by the heteropolyhedral open MT -framework formed by two types of M O 6 -octahedra and one type of MoO 4 -tetrahedron. Both M O 6 -octahedra are predominantly occupied by hafnium with the admixture of cobalt, but characterized by the different ratio between them. Large Rb + cations fill the large cavities and occupy A (1)O 9 - and A (2)O 12 -polyhedra. The topological features of the heteropolyhedral open MT -framework in related molybdates with the general formula A x B y C z (MoO 4) n are discussed. [Display omitted] • A new triple molybdate, Rb 5 Hf 1.5 Сo 0.5 (MoO 4) 6 , was synthesized. • The topological features of triple molybdates with the general formula A x B y C z (MoO 4) n are discussed. • The stoichiometry of triple molybdates was analysied. [ABSTRACT FROM AUTHOR]

New silver-based representatives of the larderellite and veatchite families, Ag 2 B 10 O 14 (OH) 4 ∙H 2 O (1) and Ag 2 B 5 O 8 (OH)∙H 2 O (2) respectively, have been prepared using a soft hydrothermal synthetic approach inside a sealed silica tube. Both structures are built of the pentaborate groups yet exhibit various dimensionality: 2D for 1 and 1D for 2. The silver atoms in 1 exhibit noticeable anharmonicity approximated using Gram–Charlie approach. 1 was additionally characterized by thermal analysis, high-temperature X-ray powder diffraction and IR spectroscopy. Thermal expansion of 1 is strongly anisotropic (α 11 = 38, α 22 = −13, α 33 = 14 × 10−6 °С−1) which is related with the hinge mechanism of the larderellite chains from corner-sharing pentaborate groups. Topology and complexity analysis of these compounds within the larderellite and veatchite families is presented. [Display omitted] • A new modification of soft hydrothermal synthesis has been proposed. • Ag 2 B 10 O 14 (OH) 4 ∙H 2 O and Ag 2 B 5 O 8 (OH)∙H 2 O belong to the larderellite and veatchite families. • Thermal expansion anisotropy of Ag 2 B 10 O 14 (OH) 4 ∙H 2 O is caused by the hinge mechanism. [ABSTRACT FROM AUTHOR]

Single crystals of compounds based on novel microporous heteropolyhedral frameworks containing Ce and Er were synthesized hydrothermally and their structures were determined. The triclinic unit cell parameters of K 7 [Ce 3 (Si 12 O 32)]⋅2H 2 O and K 7 [Er 3 (Si 12 O 32)]⋅2H 2 O, respectively, are as follows: a = 6.9833(2), 6.8334(3) Å, b = 11.4171(3), 11.4474(3) Å, c = 11.6988(4), 11.4792(3) Å, α = 87.632(2), 88.501(2)°, β = 87.546(3), 89.086(3)°, γ = 78.732(2), 79.711(3)°; V = 913.40(5), 883.16(5) Å3, space group P -1. Structural models were refined to R = 6.52 and 4.74%, respectively. The crystal structures are similar to reported compounds with the general formula K 7+ x [ Ln 3 (Si 12 O 32)]Ø x ⋅ n H 2 O and are based on (Si 12 O 32) layers of silicate tetrahedra that are one tetrahedron wide linked by Ln O 6 octahedra and Ln 2 O 10 dimers of octahedra into a heteropolyhedral framework. The structures contain two systems of parallel channels that contain potassium cations and water molecules. Topological analysis indicates the frameworks are formed by condensation of the sequence of tiles [46][34.43.63] 2 [34.48.68.82]. Bond valence sums show partial oxidation of Ce3+ to Ce4+, as previously observed by XANES. Luminescence spectra for K 7 [Er 3 (Si 12 O 32)]⋅2H 2 O indicate emission bands are related to the transitions from the 2 H 11/2 and 4 S 3/2 exited states to the 4 I 15/2 ground state. A short review of all potassium containing lanthanide silicate compounds, most of which have heteropolyhedral frameworks, is provided in which twenty-four chemical families of isostructural compounds are grouped according to the type of silicate anion. Image 1 • Cerium and erbium compounds of K 7+ x [ Ln 3 (Si 12 O 32)]Ø x ⋅ n H 2 O family with microporous heteropolyhedral frameworks were synthesized. • Luminescence spectroscopy data for the Er-containing compound were measured. • Crystal chemical comparison for all potassium containing lanthanide silicate compounds was provided. [ABSTRACT FROM AUTHOR]

Abstract The crystal structure of manganonaujakasite was studied by single crystal X-ray analysis and infrared spectroscopy using a holotype sample with the empirical chemical formula (Na 5.96 Ca 0.01) (Mn 0.53 Fe 0.49)Al 3.95 Si 8.03 O 26.00. The monoclinic unit cell parameters are: a = 15.029(1) Å, b = 7.999(1) Å, c = 10.467(1) Å, β = 113.551(1)°; V = 1153.47(15) Å3, space group C 2/ m , Z = 2. The microporous crystal structure of manganonaujakasite is similar to that of naujakasite and is based on tetrahedral [Al 4 Si 8 O 26 ]-double layers which are linked via isolated (Mn,Fe)O 6 -octahedra to form a heteropolyhedral framework containing two systems of parallel wide channels. The naujakasite-type framework topologically relates to the ATV -type of AlPO 4. Both are built from the same t - kah [63] and t - lov [42.62] tiles and are characterized by similar one-dimensional composite building units represented by the narsarsukite-type nsc -chain. The comparative data for the frameworks of naujakasite- and ATV -types are given. Graphical abstract Image 1 Highlights • The microporous crystal structure of manganonaujakasite was studied. • The naujakasite-type framework is topologically related to the ATV -type. • Topological analysis shows that both naujakasite and ATV-type framework are built by the same t - kah and t - lov tiles and characterized by similar one-dimensional CBU representing by the nsc -chain. [ABSTRACT FROM AUTHOR]

Single crystals of a novel Bi Ni phosphate Ni(BiO) 2 (PO 4 )(OH) were synthesized by a hydrothermal method in Bi 2 O 3 NiO K 2 O P 2 O 5 system and characterized by X-ray structure analysis and IR and Raman spectroscopy. This compound crystallizes in a namibite type structure with triclinic unit-cell parameters, a = 6.3220 (3) Å, b = 6.9043 (4) Å, c = 7.5641 (5) Å, α = 90.483 (5)°, β = 107.219 (5)°, γ = 110.758 (5)°; V = 292.51 (3) Å 3 ; space group P 1 ¯ (No. 2). Crystal structure is refined to final R 1 = 4.09 using 1637 I > 2σ( I ). The structure contains infinite chains {Ni(OH)(PO 4 )} ∞ built of corner-sharing NiO 6 octahedra. Microscopic calculations of the intra- and interchain J (Ni Ni) exchange parameters suggests possible S = 1 antiferromagnet chain behavior of this compound at low temperatures. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new K, Eu-silicate was synthesized using hydrothermal techniques. [•] The X-ray structure analysis was performed using single crystal diffraction data. [•] The new compound represents the new structure type. [Copyright &y& Elsevier]

Ion-exchange properties of natural caryochroite (Na,Sr) 3 {(Fe,Mg)2+ 10 (OH) 6 [TiO(Si 6 O 17)(OH) 0.5 ] 2 }·8H 2 O, a microporous heterophyllosilicate with a one-dimensional system of broad zeolytic channels, related to nafertisite Na 3 {Fe2+ 10 (OH) 6 [TiO(Si 6 O 17)F 0.5 ] 2 }·2H 2 O, were studied in reactions with 1 N aqueous solutions of Rb, Cs, Ag, and Pb nitrates at 50 °C. In reactions with Rb+, Cs+, and Pb2+, sodium is partly replaced by nearly equivalent amounts of larger cations. In reactions with Pb2+ and Ag+, additional processes involving H 2 O molecules take place: replacement of two H 2 O molecules with Pb2+ + 2OH− and replacement of H 2 O molecule with Ag+ + OH−, respectively. The geometrical-topological analysis of ion migration pathways in the nafertisite-type structures carried out using an approach based on the Voronoi-Dirichlet partition has shown that only Na+ cations occurring at the centers of wide channels can take part in reactions with large alkaline cations proceeding in counter flows. In the reaction with Ag+, additional Na+ ions are involved. Li+ cations having a smaller radius can pass through the window between the channels, forming a 2D conducting layer. Image 1 • Ion-exchange properties of natural titanosilicate caryochroite, a microporous heterophyllosilicate with a one-dimensional system of broad zeolytic channels, were studied in reactions with 1 N aqueous solutions of Rb, Cs, Ag, and Pb nitrates at 50 °C. • Three kinds of Na+ cations in the caryochroite structure play different role in ion migration processes. • Li+ cations having a smaller radius can pass through the window between the channels, forming a 2D conducting layer. [ABSTRACT FROM AUTHOR]

The series of novel phosphors Ca 9 La(PO 4) 5 [(Si 1- x Ge x O 4)]F 2 :0.15Dy3+ with x = 0, 0.25, 0.50, 0.75 and 1 (CLPS 1- x G x F:0.15Dy3+) with apatite-type structure (space group P 6 3 / m) has been synthesized. The crystal structure and electronic structure have been studied by powder X-ray diffraction (PXRD) in combination with the atomic-scale density functional theory (DFT) calculations. A combination of Raman, nuclear magnetic resonance (29Si NMR) spectroscopy and the evolution of Dy3+ ions photoluminescent properties was used to characterize the local crystal structure features. Based on the variation of the [SiO 4 ] by [GeO 4 ] tetrahedral substitutions in the apatite-type structure, the difference in the thermal stability and decay curves of CLPS 1- x G x F:0.15Dy3+ phosphors were referred to crystal chemical stability of as-prepared compounds, which is also confirmed by the values of polyhedral distortion, bond valence sum (BVS) and DFT calculations. The present study provides new insights the synthetic methodology and fundamental characterizations into the design of new phosphors combined with theoretical methods. [ABSTRACT FROM AUTHOR]

During the search for selenium analogues of FeTe 2 O 5 Cl, the new iron (III) tellurate(IV) selenate(IV) chloride with the composition Fe[(Te 1.5 Se 0.5 )O 5 ]Cl was synthesized by chemical vapor transport (CVT) reaction and characterized by TGA-, EDX-,SCXRD-analysis, as well as IR and Raman spectroscopy. It was found that Fe[(Te 1.5 Se 0.5 )O 5 ]Cl crystallizes in the monoclinic space group P 2 1 / c with unitcell parameters a = 5.183(3) Å, b = 15.521(9) Å, c = 7.128(5) Å and β = 107.16(1)°. The crystal structure of Fe[(Te 1.5 Se 0.5 )O 5 ]Cl represents a new structure type and contains electroneutral heteropolyhedral layers formed by dimers of the [FeO 5 Cl] 8– octahedra, linked via common O-O edges, and mixed [Te 3 SeO 10 ] 4- tetramers. Adjacent layers are stacked along the b axis and linked by weak residual bonds. The new compound is stable up to 420 °C. DFT calculations predict Fe[(Te 1.5 Se 0.5 )O 5 ]Cl to be a wide-gap semiconductor with the band gap of ca. 2.7 eV. [ABSTRACT FROM AUTHOR]

Cu-doped solid solutions Ca 10.5– x Cu x (PO 4) 7 with β-Ca 3 (PO 4) 2 (β-TCP) structure were synthesized using high-temperature solid-state synthesis. Correctly characterizing the location of Cu2+ in the structure is important for a correct understanding of the biological properties formation. The limit of Ca 10.5– x Cu x (PO 4) 7 solid solutions without impurity phases was found at x = 1.5. The crystal-chemical analysis reveals that the Cu2+ ions cannot be located in the M4 site of the β-TCP-type structure due to the very distorted environment. The Cu2+ ions preferably occupy the M5 site (x ≤ 1.00) and then located in the M3 and M2 sites (x > 1.00). The chemical composition, local environment, and structural features of Ca 10.5– x Cu x (PO 4) 7 phosphates were investigated by a complex of methods. The antibacterial properties were studied on one fungus (C. albicans) and four bacteria (E. coli, E. faecalis S. aureus and P. aeruginosa). Biocompatibility tests were performed on human bone marrow mesenchymal stem cells (hMSCs). The biological response of the Cu2+ strongly depends on the occupied ion position and its concentration. The concentration-dependent behavior of the bacteria growth inhibition was observed, and the sample with x = 1.33 exhibits the highest activity between single-phase samples. Further increasing of bacteria growth inhibition is attributed to Ca 3 Cu 3 (PO 4) 4 impurity phase. Also, antimicrobial properties depend on the Cu2+ location in the β-TCP crystal structure in accordance with ion release behavior. The Cu2+ location in the large M3 polyhedra leads to a noticeable increase in ion release. Biocompatibility assays on hMSCs showed the absence of cytotoxicity in direct and indirect contact for single-phase samples. In the biphasic sample the presence of impurity Ca 3 Cu 3 (PO 4) 4 phosphate at 2 wt% causes a cytotoxicity effect. Thus, phase purity plays a critical role in understanding the regularities of bioactive properties formation. This work can be an initial basis for further investigations of the site-selective arrangement of bioactive ions, such as Cu2+ and other similar ions, in the β-TCP structure to enhance biological potential. [ABSTRACT FROM AUTHOR]

The fourth representative of the Pb 2 HgO 2 Cl 2 structure type, a novel oxybromide with the chemical formula Pb 2 CdO 2 Br 2 has been prepared via solid-state route and characterized by powder and single-crystal X-ray diffraction, and Raman and EDX spectroscopy. No analogs with M = Zn or X = I have been observed as yet, though chemical interaction takes place and some new compounds are likely to be produced. The peculiarities of chemical bonding within the Pb 2 M O 2 X 2 family (M = Cd, Hg; X = Cl, Br) are analyzed by DFT calculations. Most likely, the main factor restricting the number of representatives for the Pb 2 HgO 2 Cl 2 structure type is the size ratio of M 2+ and X −. [Display omitted] • A novel oxybromide, Pb 2 CdO 2 Br 2 with the Pb 2 HgO 2 Cl 2 type structure has been synthesized. • The chemical bonds in compounds Pb 2 M O 2 X 2 (M = Cd, Hg; X = Cl, Br) were analyzed by DFT calculations. • The crystal chemical features of compounds are discussed. [ABSTRACT FROM AUTHOR]

Sulfate anion plays an important role in the development of inorganic phosphors and is considered as the path for for the enhancement of the luminescent properties. The heterovalent [PO 4 ]3– → [SO 4 ]2– anion substitution in the β-Ca 3 (PO 4) 2 -type compounds was realized using the "ellestadite"-type strategy called by the analogy with the apatite-type structures. The novel compounds belonging to the Ca 10.5–0.5 x – y M y (PO 4) 7– x (SO 4) x , M = Ca2+, Mg2+ and Zn2+ series have been synthesized using high-temperature solid state reaction. The used isomorphous scheme was [PO 4 ]3– + ½ Ca2+ = [SO 4 ]2– + ½ □ with the formation of the vacancy for the charge compensation. The successful incorporation of [SO 4 ]2– groups was approved by Fourier-transform infrared spectroscopy, EDX method, and powder X-ray diffraction analysis. It was found that the sulfur atoms predominantly occupied T2 sites in the anionic sublattice according to crystal structure refinement based on the analysis of interatomic distances. The photoluminescent properties were studied for the Eu3+-doped samples and it was shown that Zn2+-containing samples exhibit a 1.5 times higher intensity in comparison with Mg2+-containing substituted phosphates. Thus, a new "ellestadite"-type substitution in β-Ca 3 (PO 4) 2 -type structure significantly expands the crystal chemistry and give more insights into the deeper understanding of the dependence of luminescent properties on the cation distribution. The pathways of the [SO 4 ]2– incorporation into the crystal structures are discussed in details. [ABSTRACT FROM AUTHOR]

In this work, we present a new borate, Ag 3 B 6 O 10 Br, as well as thermal properties of two recently reported members of M 3 B 6 O 10 X family, Ag 3 B 6 O 10 (NO 3) and Na 3 B 6 O 10 I. The structure of Ag 3 B 6 O 10 Br is non-centrosymmetric, Pnm 2 1 , and exhibits a new version of packing the ionic Ag–Br and covalent B–O frameworks. The non-centrosymmetry is induced by alternation of disordered and ordered borate "layers" normal to a. The Ag–Br sublattice is also strongly disordered and exhibits pronounced ahnarmonicity of thermal vibrations modeled using the Gram – Charlier series. Thermal behavior of Ag 3 B 6 O 10 Br, Ag 3 B 6 O 10 (NO 3) and Na 3 B 6 O 10 I was characterized using variable-temperature powder X-ray diffraction and thermal analysis. The thermal behavior of Ag 3 B 6 O 10 Br (α a = −0.5, α b = −7.4, α c = 41.5 at 200°С), Ag 3 B 6 O 10 (NO 3) (α a = 4.5, α b = 4.8, α c = 31.8 at 200°С), and Na 3 B 6 O 10 I (α a = 9.4, α b = −1.2, α c = 48.3 at 200°С) is strongly anisotropic due to the alignment of the hexaborate B 6 O 13 groups in the structure. [Display omitted] • A new non-centrosymmetric borate, Ag 3 B 6 O 10 Br was prepared. • Cationic [Ag 3 Br]3+sublattice shows strongly anharmonic displacement parameters. • Thermal expansion of Ag 3 B 6 O 10 X, X = Br, NO 3 , and Na 3 B 6 O 10 I is anisotropic. [ABSTRACT FROM AUTHOR]

Single crystals of four new potassium rare earth tellurite chlorides, [(Ln,K) 1- x Ln 11 (TeO 3) 12 ]K 6 Cl 16+ y (Ln = Pr, Sm, Gd, and Ho), have been prepared via molten salt synthesis. From the structural viewpoint, they belong to a numerous family of complex rare-earth (and Bi) selenite and tellurite halides featuring complex [(Ln,M) 12- x (ChO 3) 12 ] building blocks interleaving with various halide or metal-halide slabs. Similar to the formally isostructural Rb- and Cs-containing analogs, in the new series of nearly isostructural compounds, the [Ln 12- x (TeO 3) 12 ] slabs alternate with [K 6 Cl 16+ x ] counterparts derived from the CsCl archetype. We discuss the overall trends in the structural chemistry of these layered chalcogenite halides. [Display omitted] • Four new layered potassium rare earth tellurite chlorides have been synthesized. • The crystal structures have been refined. • The overall trends in the structural chemistry of these compounds are discussed. [ABSTRACT FROM AUTHOR]

A new triclinic layered borate, |Ag 4 Br|@[B 7 O 12 ], has been prepared by glass crystallization and slow cooling stoichiometric melts in evacuated silica ampoules. The structure is based upon a layered borate anion 7:∞2 [(4: 2Δ + 2 T) + (3: 2Δ + T)] with an architecture yet not observed among inorganic borates. The layers consist of two parts comprised of tri- and tetraborate groups; it is ∼7 Å thick and oriented parallel to (001). The interlayer space is filled by the cationic [Ag 4 Br]3+sublattice exhibiting disorder and anharmonicity at the silver sites. The new compound was characterized by thermal analysis, high-temperature powder X-ray diffraction, vibrational and UV–Vis–NIR spectroscopy, as well as DFT calculations. For the triclinic unit cell, the eigenvalues of the thermal expansion tensor and the orientation of the thermal expansion tensor relative to the crystallographic axes are determined. The thermal expansion of the new borate bromide is strongly anisotropic, being marginal in the plane of the B–O layers (α 11 = 8.2 (1), α 22 = 4.71 (3) × 10−6 °С−1) while quite large in the normal direction (α 33 = 38.2 (3) × 10−6). [Display omitted] • A new triclinic layered borate,.|Ag 4 Br|@[B 7 O 12 ] was studied • Crystal structure is based upon a new layered borate anion. • Cationic [Ag 4 Br]3+sublattice shows strongly anharmonic vibrations. • Thermal expansion is strongly anisotropic. [ABSTRACT FROM AUTHOR]

A new cubic borate, Yb 3 [BO 3 (OH) 6 ⋅2.1H 2 O was synthesized in a multi-component hydrothermal system Yb 2 (CO 3) 3 : B 2 O 3 : P 2 O 5 = 5 : 2: 1 (T = 280 °C; P = 90–100 atm; pH = 3). The crystal structure was studied using single crystal X-ray analysis. The structure has been refined in the space group I 432, possesses the unit cell parameter a = 12.2808(15) Å. A microporous positively charged framework is formed by predominant Yb cations coordinated by O2−, OH− as a tetragonal antiprism, which are linked together via common edges and vertices. The extra framework BO 3 triangles center narrow channels, directed along 3-fold axis, are perpendicular to them and clamped between large Yb polyhedra. The large cavities with the effective cavity width 7.7 Å are filled by disordered water molecules. The crystal chemical formula could be written as (Z = 8): |(BO 3)(H 2 O) 2.1 |[Yb 3 (OH) 6. A topological analysis was performed using the ToposPro software. The framework is characterized by the following tile sequence: [34 6 [324.46.68; the calculated structural complexity parameters are: v = 48 atoms, I G = 1.500 bits/atom, and I G,total = 72.000 bits/unit cell; the framework density is 12.96 Yb/1000 Å3. The Yb-borate is similar to the tetragonal compounds with the general formula ABa 12 (BO 3) 7 F 4 (A = Li, Na) and Li x Na 1-x Ba 12 (BO 3) 7 F 4 , which are characterized by co-called "anti-zeolite" frameworks, formed by Ba2+ cations. The excess of water in the structure of the new borate compound Yb 3 [BO 3 (OH) 6 ⋅2.1H 2 O is determined by its zeolitic nature and by hydrothermal growth conditions. Image 1 • A new cubic borate Yb 3 [BO 3 (OH) 6 ⋅2.1H 2 O was synthesized hydrothermally. • Anionic part is presented by isolated BO 3 triangles. • Yb atoms form a microporous cationic positively charged "anti-zeolite" framework. • Water molecules fill large cavities of width 7.7 Å connected by channels. [ABSTRACT FROM AUTHOR]