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Saccoite, Ca2Mn3+2F(OH)8⋅0.5(SO4), is a new mineral found at the N'Chwaning III mine, Kalahari Manganese Field, Northern Cape Province, Republic of South Africa. It occurs as fillings of voids in hydrothermally altered manganese ore (comprising mostly of bixbyite and baryte). Further associated minor minerals are braunite, gypsum, chlorite, sturmanite and ettringite. Saccoite forms small needles, felted crystal masses or crusts. The new mineral is olive green, transparent, with white streak and vitreous lustre. No luminescence is observed. Saccoite is uniaxial (–) with refractive indices at 589(1) nm of ω = 1.705(5) and ɛ = 1.684(2). Pleochroism is distinct, i.e. bluish green (ω) and yellowish green (ɛ). The chemical composition was studied by means of an electron probe micro-analyser (EPMA) using wavelength-dispersive X-ray spectrometry (WDS). The empirical mineral formula is Ca2.06Mn3+1.78Cu0.10Mg0.07F0.97(OH)8.02(SO4)0.39. The unit-cell dimensions of saccoite (space group P4/ncc) are a = 12.834(3) Å, c = 5.622(2) Å, V = 926.0(4) Å3), and the calculated mass density is 2.73 g⋅cm–3. Saccoite exhibits a heteropolyhedral framework structure that is composed of edge- and corner sharing CaF2(OH)6 and M(OH)6 polyhedra (M = Mn3+ and Cu2+) with large channels along [001], which host disordered and only partially occupied groups, especially SO42–. The hydrogen atoms of the OH groups point into the channel to form hydrogen bonds with the channel anions. Ca–F distances are ~2.3 Å, the Ca–OH distances in the range of 2.44–2.58 Ǻ, and the M(OH)6 octahedron is strongly 4+2 Jahn-Teller distorted (4 × ~1.92 Å, 2 × 2.27 Å). The F atom is tetrahedrally coordinated to calcium atoms. The strongest lines in the powder X-ray diffraction pattern [d in Å (relative intensity) (hkl)] are: 9.0735 (35) (110), 4.5370 (95) (220), 4.0644 (20) (310), 3.0105 (100) (321), 2.8117 (20) (002), 2.7242 (75) (411), 1.9755 (35) (611), and 1.8142 (20) (550).

Katsarosite, ideally Zn(C2O4)·2H2O, named for Īraklīs Katsaros, is a new mineral found at the Esperanza Mine in the Kaminiza area of the Lavrion Mining District, Greece. Katsarosite usually occurs directly on sphalerite or embedded in jarosite and/or hydrozincite, often intimately intergrown with gypsum and overgrown by goslarite and/or epsomite. Crystal aggregates are mostly fine granular to earthy, with individual crystals being usually rounded with an average diameter of 30 µm, sometimes prismatic along [001] or platy, exhibiting the indistinct forms {100}, {001}, {110}, and {101}. Katsarosite is malleable with a Mohs hardness of 1½ – 2 and exhibits a perfect cleavage on {110}; the fracture is uneven in all other directions. The colour depends on the iron (Fe2+) content, ranging from pure white in almost Fe-free samples to yellow in Fe-rich specimens. It has a resinous luster and a white streak; no luminescence has been observed under either short- or long-wave ultraviolet radiation. Katsarosite is optically biaxial (+). Refractive indices measured at a wavelength of 589 nm are nα = 1.488(2), nβ = 1.550(2), nγ = 1.684(2), with 2Vobs = 71(3)°. Chemical analysis gave on average C2O3 38.32 wt%, ZnO 38.99 wt%, FeO 1.92 wt%, and H2O 19.04 wt% (the latter was deduced based on the crystal-structure refinement), with traces of MgO and MnO. The new mineral is readily soluble in dilute acids. Katsarosite is monoclinic, space group C2/c, with unit-cell parameters a = 11.768(3), b = 5.3882(12), c = 9.804(2) Å, β = 127.045(8)°, V = 496.2(2) Å3 (Z = 4). The strongest lines in the Gandolfi X-ray powder pattern [dobs in Å, Iobs/I100, (hkl)] are: 4.6745, 100, (200); 4.7678, 94, (20$$\overline{2 }$$ 2 ¯ ); 2.9533, 51, (40$$\overline{2 }$$ 2 ¯ ); 4.7030, 37, (1 $$\overline{1 }\,\overline{1 }$$ 1 ¯ 1 ¯ ); 3.9266, 33, (002); 3.5686, 27, (111); 2.6574, 22, (1 $$\overline{1 }\,\overline{3 }$$ 1 ¯ 3 ¯ ); 3.5992, 8, (1 $$\overline{1 }\,\overline{2 }$$ 1 ¯ 2 ¯ ); 2.7032, 4, (020). The crystal structure was refined based on single-crystal X-ray diffraction data to R(F) = 0.08. The observed mass density of 2.50(2) g cm−3 compares well with the calculated value (2.508 g cm−3). Katsarosite belongs to the humboldtine group, whose crystal-structure type is well described for both isotypic minerals and synthetic compounds in the literature. The atomic arrangement in Zn(C2O4)·2H2O is characterized by chains consisting of isolated ZnO6 octahedra which are alternately linked along [010] via oxalate anions. These chains are interconnected through hydrogen bonds only, with Ow···O (with Ow denoting the O atom of the H2O molecule) donor–acceptor distances of ~ 2.8 Å.

Philipsburgite has been redefined as the intermediate member of the goldhillite–philipsburgite–kipushite isomorphous series with the ideal formula Cu5Zn[(AsO4)(PO4)](OH)6⋅H2O due to the site-selective As–P substitution. The new mineral goldhillite, ideally Cu5Zn(AsO4)2(OH)6⋅H2O [or Cu5Zn(AsO4)(AsO4)(OH)6⋅H2O], is the arsenate end-member of this series. Goldhillite occurs on fracture surfaces in a rock comprised mostly of quartz with iron hydroxides in association with mixite, cornwallite and conichalcite. Goldhillite forms transparent, bright emerald-green, tabular crystals with vitreous lustre, flattened on {100}, up to 1 mm across and in rosettes up to 1.5 mm. The mineral is brittle with uneven fracture and perfect cleavage on {100}; the Mohs hardness is 3.5. The calculated density for the holotype is 4.199 g cm–3. The Raman spectrum is consistent with the presence of H2O-molecules, OH-groups, AsO4 tetrahedra and traces of PO4. Electron microprobe analyses of goldhillite (H2O content based on the crystal structure) provided: CuO 48.91, ZnO 13.18, As2O5 26.06, P2O5 3.25, H2O 8.97, total 100.37 wt.%. The empirical formula for goldhillite based on O = 15 apfu is (Cu4.69Zn1.23)Σ5.92(As0.86P0.18O4)2(OH)5.61⋅H2O. The crystal structures of goldhillite and philipsburgite were determined using single-crystal X-ray diffraction data and refined to R1 = 0.054 (for 2365 I > 2σI reflections) and 0.052 (for 2308 I > 2σI reflections), respectively. Goldhillite is monoclinic, P21/c, a = 12.3573(5), b = 9.2325(3), c = 10.7163(4) Å, β = 97.346(4)°, V = 1212.59(8) Å3 and Z = 4. Philipsburgite is monoclinic, P21/c, a = 12.3095(9), b = 9.2276(3), c = 10.7195(3) Å, β = 97.137(7)°, V = 1208.16(10) Å3 and Z = 4. The strongest lines of the powder X-ray diffraction pattern of goldhillite [d, Å (I, %)(hkl)] are: 4.09 (28)(300), 3.41 (23)(12$\bar{2}$, 221, 311), 2.57 (100)(132, 11$\bar{4}$, 20$\bar{4}$), 2.17 (18)(42$\bar{3}$, 332), 1.95 (22)(432) and 1.54 (20)(13$\bar{6}$, 060). Goldhillite is named after its type locality, the Gold Hill mine, Tooele County, Utah, USA.

The hybridized lanthanide-containing molybdenum blue (Ln-MB) wheel Na4[Mo2O2(OH)4(C6H4NO2)2]2[Mo120Ce6O366H12(OH)2(H2O)76]∼200H2O ({Mo2(C6H4NO2)2}2{Mo120Ce6}) was assembled in an aqueous one-pot synthesis. The Ln-MB was hybridized with 2-picolinic acid through the generation of the organometallic counter-ion [Mo2O2(OH)4(C6H4NO2)2]2+. Control experiments demonstrated that the position of the carboxylic acid group (2-position to the N atom) in the hybridization component is critical in yielding single crystals of Ln-MB. In addition to single-crystal X-ray diffraction (XRD) analysis, which revealed a `Japanese rice-ball'-shaped Ln-MB as the anion, elemental analyses, IR spectroscopy, and thermogravimetric analysis (TGA) were performed to confirm its structure and composition. Bond-valence-sum calculations (BVS) revealed that {Mo2(C6H4NO2)2}2{Mo120Ce6} is composed of a 24-electron reduced anionic ring, which was confirmed by Vis–NIR spectroscopy.

Alumino-oxy-rossmanite, ideally ☐Al3Al6(Si5AlO18)(BO3)3(OH)3O, is here described as a new member of the tourmaline supergroup. It is an early magmatic Al-rich oxy-tourmaline from a small pegmatitic body embedded in amphibolite and biotite-rich paragneiss. This new pink tourmaline was found in a Moldanubian pegmatite (of the Drosendorf Unit) that occurs in a large quarry near the village of Eibenstein an der Thaya, Waidhofen an der Thaya district, Lower Austria, Austria. The empirical formula of the holotype was determined on the basis of electron microprobe analysis (EMPA), secondary ion mass spectrometry (SIMS), spectroscopical methods (optical absorption and infrared spectroscopy), and crystal-structure refinement (SREF) as X(☐0.53Na0.46Ca0.01) Y(Al2.37Mn0.213+Li0.16☐0.14Mn0.072+Fe0.033+Fe0.012+Ti0.014+) ZAl6(Si5.37Al0.41B0.22O18)(BO3)3V[(OH)2.77O0.23] W[O0.80(OH)0.15F0.05]. Chemical composition (wt%) is: SiO2 33.96, TiO2 0.10, Al2O3 47.08, B2O3 11.77, FeO 0.08, Fe2O3 0.23, MnO 0.52, Mn2O3 1.70, CaO 0.04, Li2O 0.25, ZnO 0.03, Na2O 1.51, H2O 2.79, F 0.09, total 100.11. The presence of relatively high amounts of trivalent Mn in alumino-oxy-rossmanite is in agreement with the observation that the OH groups are present at a lower concentration than commonly found in other Al-rich and Li-bearing tourmalines. The crystal structure of alumino-oxy-rossmanite [space group R3m; a = 15.803(1), c = 7.088(1) Å; V = 1532.9(3) Å3] was refined to an R1(F) value of 1.68%. The eight strongest X-ray diffraction lines in the (calculated) powder pattern [d in Å (I) hkl] are: 2.5534 (100) 051, 3.9508 (85) 220, 2.9236 (78) 122, 4.1783 (61) 211, 2.4307 (55) 012, 2.0198 (39) 152, 1.8995 (30) 342, 6.294 (28) 101. The most common associated minerals are quartz, albite, microcline, and apatite. Beryl and, in places, schorl are also found as primary pegmatitic phases. Because of the low mode of associated mica (muscovite), we assume that the silica melt, which formed this pegmatite, crystallized under relatively dry conditions, in agreement with the observation that alumino-oxy-rossmanite contains a lower amount of OH than most other tourmalines. This new member of the tourmaline supergroup exhibits the most Al-rich end-member composition of the tourmaline supergroup (theoretical content: ~54 wt% Al2O3). The significant content of tetrahedrally coordinated Al could reflect the relatively high-temperature conditions (~700 °C) inferred for crystallization of the pegmatite. Alumino-oxy-rossmanite was named for its chemical relationship to rossmanite, ☐(LiAl2)Al6(Si6O18) (BO3)3(OH)3(OH), which in turn was named after George R. Rossman, Professor of Mineralogy at the California Institute of Technology (Pasadena, California, U.S.A.).

Crystals of the compound LiCo(SO4)OH were synthesised at low-hydrothermal conditions, and the crystal structure was determined and refined from single crystal X-ray diffraction data. LiCo(SO4)OH crystallises monoclinic, space group P21/c, Z = 4, a = 9.586(2), b = 5.425(1), c = 7.317(1) Å, β = 109.65(1)°, V = 358.3 Å3, wR2 = 0.0485 (2215 unique reflections, 78 variables). The structure is built from chains of edge-sharing, quite strongly bond-length and -angle distorted Co(OH)3O3 octahedra ( = 2.126 Å), which are further linked by common corners, hydrogen bonds, and by properly shaped SO4 tetrahedra ( = 1.476 Å) to sheets parallel (100). These sheets are connected to a three-dimensional framework by sharing corners with distorted LiO4 polyhedra ( = 1.956 Å). Apart from the isotypic sulfates of Mn2+ and Fe2+, only the molybdate LiCd(MoO4)OH crystallises isostructural with LiCo(SO4)OH. However, a very close structural relationship exists with the rare mineral hodgkinsonite, Zn2Mn(SiO4)(OH)2, yielding crystal chemically very uncommon topological equivalents of Zn2+ ≡ S6+ and Si4+ ≡ Li+, aside from the expectable substitution Mn2+ ≡ Co2+. Polarised optical absorption spectra of LiCo(SO4)OH reveal that the dominating spin-allowed 4T1(P) band system of Co2+ (d7 configuration) is strongly split up and covers a prominent part (~ 15,500–24,500 cm−1) of the visible spectral range, in accordance with the significant distortion of the Co(OH)3O3 polyhedron. The spectra are interpreted in terms of the Superposition Model of crystal fields, yielding a new set of intrinsic and interelectronic repulsion parameters for Co2+.

A novel tungstoantimonate, [Na5(H2O)18{(HOCH2)2CHNH3}2][SbVWVI 6O24] (SbW6 ), was synthesized from an aqueous solution and structurally characterized by single-crystal X-ray diffraction, which revealed C2/c symmetry. The structure contains two serinol [(HOCH2)2CHNH3]+ and five Na+ cations, which are octahedrally surrounded by 18 water molecules, and one [SbVWVI 6O24]7− anion. The serinol molecules also play a critical role in the synthesis by acting as a mild buffering agent. Each of the WVI and SbV ions is six-coordinated and displays a distorted octahedral motif. A three-dimensional supramolecular framework is formed via hydrogen-bonding interactions between the tungstoantimonates and cations. Powder X-ray diffraction, elemental analysis, thermogravimetric analysis and IR spectroscopy were performed on SbW6 to prove the purity, to identify the water content and to characterize the vibrational modes of the crystallized phase.

The two new copper(II) salts Cu(SeO 4) and Cu(SeO 3 OH) 2 ·6H 2 O were synthesized at low-temperature hydrothermal conditions (220 °C), and room temperature, respectively. Their atomic arrangements were studied based on single-crystal X-ray investigations [P2 1 /n, a = 4.823(1), b = 8.957(2), c = 6.953(1) Å, β = 94.82(1)° Z = 4; P – 1, a = 6.133(1), b = 6.303(1), c = 8.648(2) Å, α = 70.45(1), β = 84.60(1), γ = 73.44(1)°, Z = 1]. Cu(SeO 4) adopts the MnAsO 4 structure type. It exhibits structural as well as topological relations with two formerly known isochemical compounds. They crystallize in the structure type ZnSO 4 (mineral name zincosite, Pnma) respectively NiSO 4 (Cmcm). The two minerals dravertite, CuMg(SO 4) 2 , and hermannjahnite, CuZn(SO 4) 2 , are isotypic with CuSeO 4-P2 1 /n; interestingly, also α-NaCu(PO 4) belongs to this structure type: some rotation of the XO 4 group allows a supplementary position for the Na atom. ― Cu(SeO 3 OH) 2 ·6H 2 O represents a new structure type. The protonated selenate group shows an extended Se―O h bond distance (1.695 Å) as compared to the other Se―O bonds (1.614 to 1.626 Å). One OH dipole of the three independent H 2 O molecules represents a rather free hydrogen bond. For the other H atoms, the O―H···O lengths vary from 2.585 to 2.799 Å. Interestingly, the distance O w 7···O w 7 of only 2.791 Å does not represent an edge in a coordination polyhedron and it is not preliminary involved in the hydrogen bond scheme. All Cu 2+ ions in the two title compounds are in a pronounced [4+2] coordination. The Cu 2+[4+2] atoms in Cu(SeO 4) are linked to chains along [100]; in Cu(SeO 3 OH) 2 ·6H 2 O they are not connected among each other.

The ever‐growing interest in sustainable energy sources leads to a search for an efficient, stable, and inexpensive homogeneous water oxidation catalyst (WOC). Herein, the PO4 3− templated synthesis of three abundant‐metal‐based germanotungstate (GT) clusters Na15[Ge4PCo4(H2O)2W24O94] ⋅ 38H2O (Co4), Na2.5K17.5[Ge3PCo9(OH)5(H2O)4W30O115] ⋅ 45H2O (Co9), Na6K16[Ge4P4Co20(OH)14(H2O)18W36O150] ⋅ 61H2O (Co20) with non‐, quasi‐, or full cubane motifs structurally strongly reminiscent of the naturally occurring {Mn4Ca} oxygen evolving complex (OEC) in photosystem II was achieved. Under the conditions tested, all three GT‐scaffolds were active molecular WOCs, with Co9 and Co20 outperforming the well‐known Na10[Co4(H2O)2(PW9O34)2] {Co4P2W18} by a factor of 2 as shown by a direct comparison of their turnover numbers (TONs). With TONs up to 159.9 and a turnover frequency of 0.608 s−1 Co9 currently represents the fastest Co‐GT‐based WOC, and photoluminescence emission spectroscopy provided insights into its photocatalytic WOC mechanism. Cyclic voltammetry, dynamic light scattering, UV/Vis and IR spectroscopy showed recyclability and integrity of the catalysts under the applied conditions. The experimental results were supported by computational studies, which highlighted that the facilitated oxidation of Co9 was due to the higher energy of its highest occupied molecular orbital electrons as compared to Co4., Water oxidation: The stabilization of non‐, quasi‐ and full‐cubane topologies in three CoII germanotungstates (Co‐GT) [Ge4PCo4(H2O)2W24O94]15− (Co4), [Ge3PCo9(OH)5(H2O)4W30O115]20− (Co9), [Ge4P4Co20(OH)14(H2O)18W36O150]22− (Co20) via PO4 3− and GT lacunary ligands is reported. The Co‐GTs are active molecular water oxidation catalysts with Co9 and Co20 outperforming the non‐cubane [Co4(H2O)2(PW9O34)2]10− by a factor of 2, showing the structural and functional similarity of the GT‐encapsulated cubanes to the {Mn4Ca} oxygen evolving complex.

The new högbomite-group mineral magnesiohögbomite-6N12S, ideally Mg5Al11TiO23(OH), was found in calcite “vein-dikes” at the DeWitts Corners occurrence, lots 10 and 11, concession 1, Bathurst Township, Ontario, Canada. It forms tabular and short-prismatic crystals up to 5 mm in size. The major forms are pinacoid {0001} and hexagonal pyramid {11${\bar 2}$1}, sometimes modified by hexagonal prism {11${\bar 2}$0}. The associated minerals are magnesiohögbomite-2N3S, spinel, corundum, diopside, magnesio-hastingsite, pargasite, clinochlore and calcite. Magnesiohögbomite-6N12S is dark brown to black with brown streak and vitreous lustre. It has no cleavage and its fracture is uneven. The Mohs hardness is 6½. Dcalc is 3.87 g/cm3. The infrared spectrum is reported. The composition (wt.%) is MgO 13.09, ZnO 0.46, FeO 11.91, Fe2O3 6.84, Al2O3 62.70, TiO2 4.44, H2O 0.99, total 100.43. The empirical formula calculated on the basis of 17 cations, excluding H+, is (Mg2.95Fe2+1.51Al0.49Zn0.05)Σ5(Al10.71Fe3+0.78Ti0.51)Σ12O23(OH). The simplified formula is (Mg,Fe)5(Al,Fe,Ti)12O23(OH). The mineral is trigonal, R${\bar 3}$m, a = 5.7194(2), c = 83.069(5) Å, V = 2353.3(2) Å3 and Z = 6. The strongest reflections of the powder X-ray diffraction pattern [d,Å(I)(hkl)] are: 2.921(26)(0.1.23), 2.863(49)(110), 2.687(29)(0.1.26), 2.547(31)(0.1.$\overline{28}$) and 2.434(100)(1.1.18). The crystal structure was solved and refined from single-crystal X-ray diffraction data to R1 = 0.022. It is composed of alternating spinel (S) and nolanite (N) modules in the sequence 3 × (NSSNSS). The sequence of cubic ‘c’ and hexagonal ‘h’ closed-packed oxygen layers is 3 × (cccccchcccch). It is the first polysome in the högbomite supergroup with such a sequence.

A new mineral, nioboheftetjernite, ideally ScNbO4, was found in the Befanamo pegmatite, Analamanga, Madagascar. It occurs as anhedral grains and very crude elongated crystals up to 200 μm in length in an intergrowth with rossovskyite, ilmenite, rutile, thortveitite, euxenite-(Y), feldspar, and quartz. The mineral is black with dark-brown to black streak and submetallic luster. It has no cleavage and its fracture is uneven. Dcalc is 5.855 g/cm3. The Raman spectrum and reflectance data are reported. The chemical composition (wt.%) is MgO 0.06, MnO 2.49, Fe2O3 12.14, Sc2O3 11.34, TiO2 5.94, SnO2 1.45, Nb2O5 32.23, Ta2O5 29.93, WO3 3.38, total 98.96. The empirical formula calculated on the basis of 4 O apfu is (Sc0.40Fe3+0.37Ti0.15Mn2+0.08)Σ1.00(Nb0.58Ta0.33W0.03Ti0.03Sn0.02)Σ0.99O4. The simplified general formula is (Sc,Fe3+)(Nb,Ta)O4. Nioboheftetjernite is monoclinic, P2/c, a = 4.7092(3), b = 5.6531(4), c = 5.0530(4) Å, β = 90.453(3)°, and V = 134.515(17) Å3. The strongest reflections of the powder X-ray diffraction pattern [d,Å(I)(hkl)] are: 4.722(22)(100), 3.776(22)(011), 3.628(44)(110), , 2.938(83)(111), 2.472(30)(021), and . The crystal structure, refined from single-crystal X-ray diffraction data (R1 = 0.016), is of the “wolframite” type. The mineral is named as the Nb-analogue of heftetjernite, ScTaO4.

A strongly dichroic (vivid blue to near-colourless) tourmaline specimen from the Elahera gem field, central Sri Lanka, was identified as dravite. The sample shows strong Fe2+-related optical absorption (E⊥c) in the red range and comparably weak red emission due to Cr3+. The discovery of virtually Cu-free blue dravite (with a Li content of only about 3 ppm) shows that blue colour in gem tourmaline is not restricted to Cu- and/or Fe-bearing elbaite and other lithium tourma-lines. Also, this study reconfirms the usefulness of Raman spectroscopy for non-destructive mineral identification. The sensitivity of Raman shifts of O–H stretching bands to their nearest-neighbour cations allowed us to exclude the presence of significant amounts of Li ions, even before obtaining results of light-element analysis.

Zinc-rich fluor-elbaite from Piława Górna, Poland, was studied by electron microprobe (EPMA), single-crystal X-ray diffraction (SREF), and Raman spectroscopy (RS) to check the possibility of the application of RS to draw crystal-chemical conclusions for Al-rich and Li-bearing tourmalines on basis of the O–H stretching vibrations in the spectral range 3400–3800 cm–1. This tourmaline, forming a thin metasomatic zone around gahnite, features varying compositions with a ZnO content reaching in the studied fragment of 5.70(12) wt%. The crystal structure of this Zn-rich fluor-elbaite [a = 15.921(1), c = 7.127(1) Å] was refined with a R1 value of 1.67%. Its formula was determined on the basis of electron-microprobe and structure refinement as (Na0.84☐0.14Ca0.01)XΣ1.00(Al1.06Li0.84Zn0.69Fe0.322+Mn0.09)YΣ3.00AlZ6(BO3)3(Si6TO18)(OH)3V(F0.65OH0.26O0.09)W. The deconvolution of the O–H stretching vibration bands, performed by fitting of an input model of component bands with Gaussian function shapes for the empirical spectrum, indicates that each of the three maxima assigned for VOH bonded to YAl3+, Y2+, and YLi+ and with the total integral intensity of at least 75% of the total OH content could be resolved into 1 to 3 bands, depending on the X-site occupation (vacancies, Na+, and Ca2+). The deconvolution indicates further that several low intense bands of WO–H modes above a Raman shift of 3600 cm–1, totally reaching ≤25%, are dependent on the occupation of triplets of YYY cations bonded to the hydroxyl. These WO–H modes are also influenced by the X-site occupation. Due to ordering of all octahedral cations (except Al) at the Y site and a complete occupation of the Z site by Al and the V site by OH, it seems possible to evaluate the Li and OH contents in a Al-rich and Li-bearing tourmaline directly from the Raman spectrum. By using the ratio VOHIYAlZAlZAl/(VOHIYZZ + WOHIYYY) as evaluated from RS, corresponding to the ratio YAl/V+WOH in the crystal, the formula of the Zn-rich fluor-elbaite can be calculated as (Na0.85☐0.14Ca0.01)XΣ1.00(Al1.11Y1.112+Li0.78)YΣ3.00AlZ6(BO3)3(Si6O18)(OH)3(F0.65OH0.13O0.22), where Y 2+ = Zn + Fe + Mn. The formula, determined only on basis of EPMA and deconvolution of RS in the O–H stretching bands, corresponds very well (≤1 SD range of EPMA) to the formula determined on basis of EPMA and SREF. This result implicates that the O–H stretching vibrations, measured by Raman spectroscopy, could be applied for Al-rich and Li-bearing tourmalines as a useful tool for providing additional information for determining the crystal-chemical formula. It is also very helpful when crystal structural data are not available.

The first synthetic pathway using a series of four nonlacunary 4f-heterometal-substituted polyoxotungstate clusters Na21[(Ln(H2O)(OH)2(CH3COO))3(WO4)(SbW9O33)3]·nH2O (NaLnSbW9; Ln = TbIII, DyIII, HoIII, ErIII, YIII) as precursors for the directed preparation of nine new 3d–4f heterometallic tungstoantimonates K5Na12H3[TM(H2O)Ln3(H2O)5(W3O11)(SbW9O33)3]·nH2O (KTMLnSbW9; TM = CoII, NiII; Ln = TbIII, DyIII, HoIII, ErIII, YIII) has been developed. Systematic studies revealed an increased K content in the aqueous acidic reaction mixture to be the key step in the cation-directed preparation of 3d–4f compounds; among those, the Co-containing members represent the first examples of KCoLnSbW9 (Ln = TbIII, DyIII, HoIII, ErIII, YIII) heterometallic tungstoantimonates exhibiting the SbW9 building block. All 13 compounds have been characterized thoroughly in the solid state by powder and single-crystal X-ray diffraction (XRD), revealing a cyclic trimeric polyoxometalate architecture with three SbW9 units encapsulating a planar triangle of LnIII ions in the case of NaLnSbW9 and a heterometallic core of one TMII and three LnIII for KTMLnSbW9 (TM = CoII, NiII; Ln = TbIII, DyIII, HoIII, ErIII, YIII). The results obtained by XRD are supplemented by complementary characterization methods in the solid state such as IR spectroscopy, thermogravimetric analysis, and elemental analysis as well as in solution by UV–vis spectroscopy. Detailed magnetic studies on the representative compounds KTMDySbW9 (TM = CoII, NiII) and KCoYSbW9 of the series revealed field-induced slow magnetic relaxation., The first step-by-step synthetic protocol using preformed 4f tungstoantimonate clusters as nonlacunary precursors for the controlled preparation and thorough characterization of a family of nine new 3d−4f heterometallic polyoxometalates [TM(H2O)Ln3(H2O)5(W3O11)(SbW9O33)3]20- (KTMLnSbW9) (TM = CoII, NiII; Ln = TbIII, DyIII, HoIII, ErIII, YIII) is reported. Magnetic studies on the DyIII-containing representatives [TM(H2O)Dy3(H2O)5(W3O11)(SbW9O33)3]20− (TM = CoII, NiII) show single-molecule-magnet behavior.

Crystals of Mn3Fe2(SeO3)6 have been synthesized in the system MnCO3-FeC2O4·2H2O-H2SeO3-H2O at 220 °C and structurally characterized by single-crystal X-ray diffraction methods. The new compound is ...

Stergiouite is a new mineral from the Plaka area in the northern part of the Lavrion Mining District, Greece. The mineral occurs as clusters of stacked, platy crystals, associated with galena, sphalerite, native arsenic and sulfur. The crystals are white to colorless, with a pearly luster and white streak. No luminescence under ultraviolet (UV) radiation is observed. Stergiouite is brittle and has a Mohs hardness of ~3. Chemical analysis gave As2O5 42.93 wt%; Sb2O5 2.45 wt%; CaO 10.90 wt%; ZnO 29.79 wt%; and H2Ocalc 13.93 wt%, which corresponds to an empirical formula Ca1.02Zn1.91((As0.95Sb0.08)O4)Σ2.03 · 4H2O. The ideal formula is CaZn2(AsO4)2 · 4H2O. Stergiouite is monoclinic, space group Pc, with unit-cell parameters a 9.416(2) A; b 5.300(1) A; c 10.893(2) A; β 91.767(10)°; V 543.36(3) A3; Z = 2. The strongest lines in the Gandolfi X-ray powder pattern [d in A, I/I100, (hkl)] are: 9.406, 100, (100); 4.619, 80, (102), (110); 3.612, 35, (20 $$ \overline{2} $$ ); 3.494, 35, (112); 2.984, 60, (21 $$ \overline{2} $$ ); 2.922, 50, (212); 2.720, 20, (004); and 2.647, 25, (020). The crystal structure was refined based on single-crystal X-ray diffraction data to R1 = 0.046, wR2 = 0.093. The observed mass density of 3.1(2) g cm−3 compares well with the calculated value (3.183 g cm−3). The framework structure of stergiouite is built up by one type of CaO2(H2O)4 octahedron and each two ZnO4 and AsO4 tetrahedra. These polyhedra share common corners to form three- and four-membered rings. A system of hydrogen bonds (O–O range: 2.70–3.02 A) further stabilizes the structure. The crystal structure of stergiouite is closely related to that of phosphophyllite [Fe[6]Zn2[4](PO4)2 · 4H2O] as well as with members of the hopeite [Zn[6]Zn2[4](PO4)2 · 4H2O] group. Stergiouite is named in honour of Vasilis Stergiou (born 1958) in recognition of his contributions to the mineralogy of the Lavrion deposits.

To increase the supramolecular cooperativity in Fe(II) spin crossover materials based on N1-substituted tetrazoles, a series of ω-(1H-tetrazol-1-yl) carboxylic acids with chain-lengths of C2–C4 were synthesized. Structural characterization confirmed the formation of a strong hydrogen-bond network, responsible for enhanced cooperativity in the materials and thus largely complete spin-state transitions for the ligands with chain lenghts of C2 and C4. To complement the structural and magnetic investigation, electronic spectroscopy was used to investigate the spin-state transition. An initial attempt to utilize the bifunctional coordination ability of the ω-(1H-tetrazol-1-yl) carboxylic acids for preparation of mixed-metallic 3d–4f coordination polymers resulted in a novel one-dimensional gadolinium-oxo chain system with the ω-(1H-tetrazol-1-yl) carboxylic acid acting as μ2-η2:η1 chelating–bridging ligand.

Polyoxometalates (POMs) provide rigid and highly symmetric coordination sites and can be used as a strategy for the stabilization of magnetic ions. Herein, we report a new member of the Keggin archetype, the Cr-centered Keggin anion [α-CrW12O40]5– (CrW12), with the unusual tetrahedral coordination of CrIII reported for the first time in POMs conferring unattended magnetic properties. POM chemistry has recently presented excellent examples of single-molecule and single-ion magnets (SMMs and SIMs) as well as molecular spin qubits; however, the majority of POM-based SIMs reported to date contain lanthanoid ions. CrW12, as the first example of a chromium(III) SIM, exhibits slow relaxation of magnetization and quantum tunneling with a single-ion magnetic behavior even above 10 K with an energy barrier for the reversal of the magnetization of 3.0 K. The first 3d-metal SIM based on a nonlacunary Keggin anion is the foundation for a new research area in POM chemistry.

Electrical resistivity (4.2–800 K), Seebeck coefficient (300–800 K), specific heat (2–110 K), Vickers hardness, elastic moduli (RT) were defined for single-phase nonstoichiometric compounds: Ti2.13Ni2Sn0.87, Zr2.025Ni2Sn0.975, and Hf2.055Ni2Sn0.945.

A detailed investigation was conducted on high-pressure (~1.4 GPa) tourmaline from an Eoalpine mafic eclogite, which occurs in the Kreuzeck Mountains, Eastern Alps, Austria. Tourmaline from this locality contains the highest amount of Sr²⁺ (up to 0.68 wt% SrO) known to date. The space group is R3m with unit-cell parameters a = 15.944(1), c = 7.202(1) Å, V = 1585.5(3) ų. Analyses by a combination of electron microprobe, optical absorption spectroscopy and crystal-structure refinement (R1 = 1.31%) result in the structural formula ^X(Na_(0.85)Ca_(0.08)Sr_(0.06)K_(0.01))_(Σ1.00)^Y(Mg_(1.68)Al_(0.70) Fe_(0.37)³⁺Ti_(0.10)⁴⁺Fe_(0.11)²⁺Ca_(0.03)Cr_(0.01)³⁺)_(Σ3.00)^Z (Al_(5.15)Mg_(0.80)Fe_(0.05)³⁺)_(Σ6.00)^T(Si_(5.82)B_(0.10)Al_(0.08)O_(18)) (BO₃)₃^V(OH)₃^W [O_(0.45)(OH)_(0.35)F_(0.20)]. The T site contains mainly Si and additionally small amounts of B and Al. According to optical absorption spectroscopy (using the band near 1120 nm), the Fe³⁺/Fe ratio is 79 ± 2%, suggesting that this high-pressure tourmaline crystallized under oxidizing conditions. It has a significant oxy-dravite component. A near-rim zone contains 0.6 wt% Cr₂O₃, 0.5 wt% PbO₂, 0.2 wt% NiO and 0.1 wt% V₂O₃. Only a small F content was found by structure refinement. There is no evidence for significant X-site vacancy in the investigated tourmaline zones. We assume that the original boron source for tourmaline crystallization in the eclogite, i.e. tourmaline-bearing pegmatites in the country-rock, were influenced by a Sr-bearing marble.

The title polyoxometalate-based organic-inorganic hybrid compound, [Na

We report on the synthesis of the tetrasubstituted sandwich-type Keggin silicotungstates as the pure Na salts Na14[(A-α-SiW10O37)2{Co4(OH)2(H2O)2}]·37H2O (Na{SiW10Co2}2) and Na14[(A-α-SiW10O37)2{Ni4(OH)2(H2O)2}]·77.5H2O (Na{SiW10Ni2}2), which were prepared by applying a new synthesis protocol and characterized thoroughly in the solid state by single-crystal and powder X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis. Proteinase K was applied as a model protein and the polyoxotungstate (POT)–protein interactions of Na{SiW10Co2}2 and Na{SiW10Ni2}2 were studied side by side with the literature-known K5Na3[A-α-SiW9O34(OH)3{Co4(OAc)3}]·28.5H2O ({SiW9Co4}) featuring the same number of transition metals. Testing the solution behavior of applied POTs under the crystallization conditions (sodium acetate buffer, pH 5.5) by time-dependent UV/vis spectroscopy and electrospray ionization mass spectrometry speciation studies revealed an initial dissociation of the sandwich POTs to the disubstituted Keggin anions HxNa5–x[SiW10Co2O38]3– and HxNa5–x[SiW10Ni2O38]3– ({SiW10M2}, M = CoII and NiII) followed by partial rearrangement to the monosubstituted compounds (α-{SiW11Co} and α-{SiW11Ni}) after 1 week of aging. The protein crystal structure analysis revealed monosubstituted α-Keggin POTs in two conserved binding positions for all three investigated compounds, with one of these positions featuring a covalent attachment of the POT anion to an aspartate carboxylate. Despite the presence of both mono- and disubstituted anions in a crystallization mixture, proteinase K selectively binds to monosubstituted anions because of their preferred charge density for POT–protein interaction., We report on the development of a new synthesis protocol to prepare the Na salts of the tetrasubstituted sandwich-type Keggin derivatives Na14[(A-α-SiW10O38)2{Co4(OH)2(H2O)2}]·37H2O (Na{SiW10Co2}2) and Na14[(A-α-SiW10O38)2{Ni4(OH)2(H2O)2}]·77.5H2O (Na{SiW10Ni2}2). Following a thorough characterization of the polyoxotungstate (POT) dimers involving single-crystal and powder X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis in the solid state and UV/vis spectroscopy and electrospray ionization mass spectrometry in solution, the water-soluble compounds (>5 mM) were applied as additives for the crystallization of proteinase K along with the tetrasubstituted monomeric Keggin-type analogue K5Na3[A-α-SiW9O34(OH)3{Co4(OAc)3}]·28.5H2O ({SiW9Co4}). Crystallographic studies on the obtained protein crystals revealed monosubstituted Keggin derivatives in all three cases bound to conserved sites of the protein, which highlights a selectivity of proteinase K toward monosubstituted Keggin POTs within a narrow range of surface charge density.

A new mineral, metathénardite, ideally Na2SO4, the high-temperature hexagonal dimorph of thénardite, a natural analogue of the synthetic phase Na2SO4(I), was found in the sublimates of active fumaroles at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure eruption, Tolbachik volcano, Kamchatka, Russia. The holotype originates from the Glavnaya Tenoritovaya fumarole in which metathénardite is associated with hematite, tenorite, fluorophlogopite, sanidine, anhydrite, krasheninnikovite, vanthoffite, glauberite, johillerite, and lammerite. The cotypes 1 and 2 are from the Arsenarnaya (with hematite, tenorite, fluorophlogopite, sanidine, euchlorine, wulffite, anhydrite, fluoborite, johillerite, nickenichite, calciojohillerite, badalovite, tilasite, cassiterite, and pseudobrookite) and the Yadovitaya (with tenorite, euchlorine, fedotovite, dolerophanite, langbeinite, krasheninnikovite, anhydrite, and hematite) fumaroles, respectively. All specimens with metathénardite were collected from areas with temperatures of 350–400 °C. Metathénardite forms hexagonal tabular, lamellar, or dipyramidal crystals (forms: {001}, {100}, {102}, and {201}) up to 3 mm combined in crusts up to several hundred cm2 in area. The mineral is transparent to semitransparent, colorless, white, light-blue, greenish, yellowish, grayish or brownish, with vitreous luster. Dmeas. = 2.72(1), Dcalc. = 2.717 g/cm3. Metathénardite is optically uniaxial (–), ω = 1.489(2), ε = 1.486(2). The empirical formulae are (Na1.92K0.05Ca0.02Zn0.01)[S0.99O4] (holotype), (Na1.54K0.22Ca0.09Cu0.01Mg0.01)[S1.00O4] (cotype 1), and Na1.65K0.11Ca0.05Cu0.04Mg0.01)[S1.01O4] (cotype 2). Admixed K and bivalent cations probably stabilize the hexagonal aphthitalite-like structure of metathénardite at room temperature. The crystal structure was solved using single crystals of all three samples, R1 = 0.0852, 0.0452, and 0.0449 for holotype and cotypes 1 and 2, respectively. The space group is P63/mmc, and the unit-cell parameters of the holotype are a = 5.3467(9), c = 7.0876(16) Å, V = 157.47(6) Å3, and Z = 2. The strongest reflections of the powder X-ray diffraction pattern [d,Å(I)(hkl)] are: 4.667(27)(100), 3.904(89)(101), 3.565(33)(002), 2.824(94)(102), 2.686(100)(110), and 1.939(35)(202). Metathénardite and thénardite clearly differ from one another in X-ray diffraction data and infrared and Raman spectra.

The structure of trigonal ferrinatrite, Na3Fe(SO4)3⋅3H2O, from the Hongshan Cu-Au deposit, Eastern Tianshan, NW China was refined in space group P $$ \overline{3} $$ based on single crystal X-ray diffraction data [a = 15 .553(2), c = 8.6616(17 ) A, V = 1814.4(5) A3, Z = 6; R1 = 0.0535]. All hydrogen atoms were located by difference Fourier methods and refined with soft restrictions for distances, but with fixed thermal isotropic displacement parameters. The atomic arrangement in ferrinatrite is based on chains along [001] consisting of isolated FeO6-octahedra corner-linked with sulfate groups. All vertices of octahedra link to tetrahedra, and half the tetrahedron vertices link to octahedra. These chains are linked by interstitial Na-ions and H2O groups. All Na atoms are coordinated to four oxygen atoms of sulfate groups and to two oxygen atoms of H2O molecules within 2.33–2.71 A; next oxygens are at distances of 2.85–3.00 A. Among six hydrogen bonds, three acceptor O-atoms of sulfate groups belong to the nearest octahedral-tetrahedral chains, and three acceptor sulfate O-atoms from the neighboring chains, which further strengthen the linkages between octahedral-tetrahedral chains. The O–H···O distances are in the range 2.86–3.13 A. The O–H stretching frequencies derived from structural data are in good consistence with the known Infrared spectra.

In the present work we investigated salt formation in the L-histidine(L-His) + HI + H2O system. Single crystals of six salts have been obtained and their crystal and molecular structures have been determined: monoclinic (L-HisH)I (I), monoclinic (L-HisH)I (II), orthorhombic (L-HisH)I (III), (L-HisH2)I2 (V), (L-HisH2)I2·H2O (VI) and (L-HisH···L-HisH2)I3 (VII). One more, a triclinic polymorph (L-HisH)I (IV) has been obtained from aqueous solution containing L-histidine and HI in presence of L-proline. Infrared spectra of all seven crystals are showed and compared. Salts formed in this system differ from the salts formed in the previously investigated L-His + HF + H2O, L-His + HCl + H2O and L-His + HBr + H2O systems. Particularly, in addition to the salts formed by singly (L-HisH) and doubly (L-HisH2) charged cations we obtained a salt with (A+···A2+) type dimeric cation. Previously salts with (A+···A2+) type dimeric cation were obtained only for mixed salts with different anions. This finding may lead to reinvestigation of salts formation with ornithine, lysine, arginine and histidine capable forming singly and doubly charged cations.

Three new compounds Zr(SeO3)(SeO4), Zr4(SeO3)(SeO4)7, and Zr3(SeO3)(SeO4)5·2H2O were synthesized at low-hydrothermal conditions (Teflon-lined steel vessels, 220 °C) from mixtures of Zr2O2(CO3)(OH)2, H2SeO4, and minor contents of water. Colorless single crystals up to several tenth of a mm in size, obtained within 1 week, were studied by single crystal X-ray techniques. Zr(SeO3)(SeO4) crystallizes in the orthorhombic space group Pbca (No. 61), with a = 8.291 (2) A, b = 9.458 (2) A, c = 15.357 (3) A, V = 1204.2 (5) A3, Z = 8, R1 = 0.0322. Zr4(SeO3)(SeO4)7 is monoclinic, space group P21/n (No. 14), with a = 5.313 (1) A, b = 10.704 (2) A, c = 10.484 (2) A, β = 104.13 (1)°, V = 578.2 (1) A3, Z = 1, R1 = 0.0172. Two independent selenium atoms are present in this structure: one forming a SeO4 tetrahedron, and the other one exhibiting mixed occupation by ¾ Se6+ and ¼ Se4+; its coordination is, therefore, partially disordered. Zr3(SeO3)(SeO4)5·2H2O crystallizes in the triclinic space group P1 (No. 1), with a = 5.273 (1) A, b = 8.079 (2) A, c = 11.959 (2) A, α = 82.60 (1)°, β = 88.27 (1)°, γ = 89.87 (1)°, V = 505.1 (1) A3, Z = 1, R1 = 0.0235, but exhibits strong centrosymmetric pseudosymmetry; the inversion center is violated only by replacement of one selenate(VI) tetrahedron by a trigonal pyramidal selenite(IV) group as pseudo-centric counterpart. Hydrogen bonds in this compound show donor–acceptor distances within the range of 2.67–2.81 A. All three framework structures are unique and built up from corner-sharing polyhedra. In all three compounds, mean cation-oxygen bond lengths (Zr[6]: 2.062 and 2.067 A; Zr[7]: 2.132, 2.137 and 2.139 A; Se4+[3]: 1.675 and 1.680 A, excluding the disordered group; Se6+[4]: 1.621–1.641 A) are comparatively short, resulting in rather high bond valence sums.

We present the synthesis and structural and computational characterization of a heteroleptic dinuclear discrete complex [Cd2(μ1,3-NCS)2(NCS)2(LI)2]·4MeOH (1·4MeOH), where LI is the product of hydrolysis of one of the 2-PyC(Ph) groups of the parent ligand 1,2-diphenyl-1,2-bis((phenyl(pyridin-2-yl)methylene)hydrazono)ethane (L), fabricated from a mixture of Cd(NO3)2·4H2O and NH4NCS in methanol. An analogous procedure but in EtOH and iPrOH yielded crystals of the heteroleptic dinuclear discrete complex [Cd2(μ1,3-NCS)2(NCS)2(L)2] (2) and the polymeric complex of the composition [Cd3(NCS)6(L)]n (3). The bulky helical ligand L in the constituting CdII based synthons has been found to exhibit a quasi-aromatic Mobius features as revealed by the electron density of delocalized bonds method as well as the extended transition state coupled with natural orbitals for chemical valence calculations. It means that a transition metal induces π-electron delocalization solely in the ligand’s part; however, the d orbitals of...

A new form of l -histidinium 5-nitrouracilate has been obtained. It crystallizes in the triclinic space group P1, with two formula units in the unit cell, as opposed to the previously reported monoclinic polymorph. The 5-nitrouracilate anions form a dimer linked with double N H⋯O type hydrogen bonds. The infrared and Raman spectra of the new triclinic and previously obtained monoclinic forms have been registered and discussed.

C18H12Br2CuN4O2, monoclinic, P21/c (no. 14), a = 11.5165(11) Å, b = 5.4369(5) Å, c = 14.4872(14) Å, V = 873.52(14) Å3, Z = 2, R gt (F) = 0.0232, wR ref (F 2) = 0.0559, T = 200 K.

To increase the supramolecular cooperativity in Fe(ii) spin crossover materials based on N1-substituted tetrazoles, a series of ω-(1H-tetrazol-1-yl) carboxylic acids with chain-lengths of C2-C4 were synthesized. Structural characterization confirmed the formation of a strong hydrogen-bond network, responsible for enhanced cooperativity in the materials and thus largely complete spin-state transitions for the ligands with chain lenghts of C2 and C4. To complement the structural and magnetic investigation, electronic spectroscopy was used to investigate the spin-state transition. An initial attempt to utilize the bifunctional coordination ability of the ω-(1H-tetrazol-1-yl) carboxylic acids for preparation of mixed-metallic 3d-4f coordination polymers resulted in a novel one-dimensional gadolinium-oxo chain system with the ω-(1H-tetrazol-1-yl) carboxylic acid acting as μ2-η2:η1 chelating-bridging ligand.

We present a model for multicomponent diffusion in ionic crystals. The model accounts for vacancy-mediated diffusion on a sub-lattice and for diffusion due to binary exchange of different ionic species without involvement of vacancies on the same sub-lattice. The diffusive flux of a specific ionic species depends on the self-diffusion coefficients, on the diffusion coefficients related to the binary exchanges, and on the site fractions of all ionic species. The model delivers explicit expressions for these dependencies, which lead to a set of coupled non-linear diffusion equations. We applied the model to diffusion of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{23}$$\end{document}23Na, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{39}$$\end{document}39K, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{41}$$\end{document}41K in alkali feldspar. To this end, gem-quality crystals of alkali feldspar were used together with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{41}$$\end{document}41K doped KCl salt as diffusion couples, which were annealed at temperatures between 800\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^\circ$$\end{document}∘ and 950\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^\circ$$\end{document}∘C. Concentration-distance data for \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{23}$$\end{document}23Na, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{39}$$\end{document}39K, and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{41}$$\end{document}41K were obtained by Time of Flight Secondary Ion Mass Spectrometry. Over the entire investigated temperature range the Na self-diffusion coefficient is by a factor of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge 500$$\end{document}≥500 higher than the K self-diffusion coefficient. Diffusion mediated by binary \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{39}$$\end{document}39K–\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{41}$$\end{document}41K exchange is required for obtaining satisfactory fits of the model curves to the experimental data, and the respective kinetic coefficient is well constrained.

The reaction of 4-nitro-3-pyrazolecarboxylic acid and Cu(OAc)2?H2O in ethanol resulted in a new coordination compound [Cu2(4-nitro-3- -pzc)2(H2O)6]2H2O (4nitro-3pzc = 4-nitro-3-pyrazolecarboxylate). The compound was investigated by means of single-crystal X-ray diffraction and infrared spectroscopy. The biological activity of the complex was also tested. In the crystal structure of [Cu2(4nitro-3-pzc)2(H2O)6]2H2O, the Cu(II) ion is in a distorted [4+2] octahedral coordination due to the Jan?Teller effect. A survey of the Cambridge Structural Database showed that the octahedral coordination geometry is generally rare for pyrazole-bridged Cu(II) complexes. In the case of Cu(II) complexes with the 3-pyrazolecarboxylato ligands, no complexes with a similar octahedral coordination geometry have been reported. Biological research based on determination of the inhibition effect of the commercial fungicide Cabrio top and the newly synthesized complex on Ph. viticola were performed using the phytosanitary method.

Voudourisite, Cd(SO4)·H2O, and lazaridisite, Cd3(SO4)3·8H2O, are two new minerals from the Esperanza Mine, Kaminiza Area, Lavrion Mining District, Greece. This small ancient mine is also the type locality of niedermayrite and katerinopoulosite. Further associated minerals are sphalerite, galena, edwardsite, chalcanthite, gypsum and greenockite. Both secondary minerals form tiny clusters or crusts and are among the latest to form in this paragenetic sequence. They are colourless or white, transparent to translucent, with a white streak and vitreous lustre. No fluorescence is observed. The minerals exhibit conchoidal fracture, no cleavage or preferred parting. The Mohs hardness is ~3 and both have brittle tenacity. Voudourisite is biaxial (–) with refractive indices at 589(1) nm of α = 1.580(2), β = 1.624(2), γ = 1.640(2), 2Vmeas.= 70(5)°, 2Vcalc.= 61° and β ~ || [010]. Lazaridisite is biaxial neutral with refractive indices at 589(1) nm of α = 1.552(2), β = 1.561(2), γ = 1.570(2), 2Vmeas.= 90(5)° and 2Vcalc.= 90°. The chemical compositions of voudourisite and lazaridisite are close to ideal with only minor amounts of copper detectable. The atomic arrangement in voudourisite (space groupP21/cwitha= 7.633(2),b= 7.458(2),c= 8.151(2) Å, β = 122.35(1)° andV= 392.0(2) Å3) is related to that of kieserite while lazaridisite (space groupC2/cwitha= 14.813(3),b= 11.902(2),c= 9.466(2) Å, β = 97.38(1)° andV= 1655.2(6) Å3) is a distinct structure-type. Calculated densities are 3.838 and 3.088 g/cm3, respectively.The strongest lines in the powder X-ray pattern [din Å (I) (hkl)] are: 4.890 (66) (110); 3.741 (25) (020); 3.578 (100) (11$\bar 2$); 3.230 (43) (200); 2.525 (33) (022); 2.395 (29) (112) for voudourisite and 6.860 (100) (200); 6.317 (72) (111); 5.965 (84) (020); 4.512 (58) (310); 3.727 (78) (202); 3.608(82)(13$\bar 1$); 3.109 (83) (40$\bar 2$); 3.020 (50) (33$\bar 1$) for lazaridisite, respectively.

A concise and efficient total synthesis of the lignan natural product larreatricin as well as an unambiguous assignment of configuration of its enantiomers are reported, resolving a long‐held controversy. Enzyme kinetic studies revealed that different polyphenol oxidases show high and remarkably divergent enantioselective recognition of this secondary metabolite.

The crystal structure of the novel Al-rich intermetallic phase Ce4Pt9Al13 was determined from single-crystal X-ray diffraction data and confirmed by powder X-ray diffraction. The compound crystallizes with its own structure type, which is a “site exchange” variant of the Ho4Ir13Ge9-type (Pearson symbol oP52, space group Pmmn, No. 59, Z = 2, lattice parameters: a = 4.1826(1) A, b = 11.4424(3) A, c = 19.8475(5) A, V = 949.88(7) A3). The magnetic properties of Ce4Pt9Al13 were determined in the temperature range 1.72–400 K. Down to the lowest temperatures studied, the compound shows a Curie-Weiss paramagnetic behavior with strong crystalline electric field contribution observed below about 200 K. The electrical conductivity in Ce4Pt9Al13 has metallic character, and at low temperatures it is governed by an interplay of strong crystal field and Kondo interactions.