Zeolitová mineralizace z Malého Semerinku u Chřibské v Lužických horách (Česká republika)

An interesting occurrence of secondary phosphates fluorwavellite, variscite and strengite in the Barrandian area has been newly discovered in Kamenný Újezd near Rokycany (Czech Republic). Phosphates crystallize on cracks of hornfels pebbles in weathered conglomerates and in cavities of quartz veins that penetrate them. Fluorwavellite forms white, needle-like, radially rayed aggregates with a diameter of up to 3 cm on the cracks and white to slightly yellowish spherical aggregates up to 1 cm in size in cavities. Variscite occurs in fissures in the form of flat radial aggregates of white colour and pearly lustre up to 0.8 mm in size. In the cavities of quartz veins, variscite forms spherical aggregates up to 0.8 mm in diameter and reniform layers of white, light beige, light gray, and light pink colours. Variscite is covered with a layer of strengite approximately 0.06 to 0.08 mm thick. The WDS quantitative analyses, X-ray powder patterns, and refined unit cell parameters are given for all described mineral phases.

Preparation and properties of two indium antimony selenides

The molecular structures of an anhydrous and dihydrate forms of a 24-atom triazine macrocycle containing proline and methine hydrazine residues, were determined by MicroED (Single Crystal Electron Diffraction, ScED, 3DED). The whole powder pattern profile decomposition (WPPD) Pawley refinement of the X-ray Powder Pattern (RT, XRPD) confirms the two crystalline forms of the macrocycle in the sample and indicates one or more additional unidentified crystalline states. The macrocycle is protonated at the triazines (pKa ∼6) by trifluoroacetic acid (TFA, pKa 0.25) to yield a dication. In the anhydrous form, the TFA anions form strong hydrogen bonds to the methine hydrazine groups (NHN=CH) while in the dihydrate the TFA anions form hydrogen bonds to water molecules. The macrocycle folds into a “taco shell” shape for both structures. The unit cell from MicroED for the anhydrous macrocycle (RT, SG P21212) is: a = 22.936(228)Å, b = 7.2766(222)Å, c = 12.4713(404) Å, V = 2081(96) Å3 and from the WPPD Pawley refinement (RT,XRPD): a = 22.754(18) Å, b = 7.475(6) Å, c = 12.562(13)Å, V = 2139(3) Å3. The dihydrate macrocycle MicroED cell (100K, SG C2) is: a = 15.074(406) Å, b = 12.206(156) Å, c = 23.8816(150) Å, β = 97.817(492)°,V = 4273(132)Å3 and from the WPPD Pawley refinement (RT) a = 15.093(3)Å, b = 12.241(3)Å, c = 23.900(6)Å, β = 98.092(14)°, V = 4379.2(2) Å3. The XRPD analysis showed that the refined unit cell parameters were consistent with the MicroED results for both forms. This study highlights the combined use of XRPD and MicroED to gain a comprehensive understanding of crystalline samples.

Chesnokovite, a new mineral species, is the first natural sodium orthosilicate. It has been found in an ussingite vein uncovered by underground mining at Mt. Kedykverpakhk, Lovozero alkaline pluton, Kola Peninsula, Russia. Natrolite, sodalite, vuonnemite, steenstrupine-(Ce), phosinaite-(Ce), natisite, gobbinsite, villiaumite, and natrosilite are associated minerals. Chesnokovite occurs as intergrowths with natrophospate in pockets up to 4 × 6 × 10 cm in size consisting of chaotic segregations of coarse lamellar crystals (up to 0.05 × 1 × 2 cm in size) flattened along [010]. The crystals are colorless and transparent. The aggregates are white to pale brownish yellowish, with a white streak and a vitreous luster. The cleavage is perfect parallel to (010) and distinct to (100) and (001). The fracture is stepped. The Mohs’ hardness is 2.5. The measured density is 1.68 g/cm3; the density calculated on the basis of an empirical formula is 1.60 g/cm3 and 1.64 g/cm3 on the basis of an idealized formula. The new mineral is optically biaxial, positive, α = 1.449, β = 1.453, γ = 1.458, 2Vmeas = 80°, and Z = b. The infrared spectrum is given. The chemical composition (Si determined with electron microprobe; Na, K, and Li, with atomic emission analysis; and H2O, with the Alimarin method) is as follows, wt %: 21.49 Na2O, 0.38 K2O, 0.003 Li2O, 21.42 SiO2, 54.86 H2O, total is 98.153. The empirical formula calculated on the basis of O2(OH)2 is as follows: (Na1.96K0.02)Σ1.98Si1.005O2(OH)2 · 7.58H2O. The simplified formula (Z = 8) is Na2[SiO2(OH)2] · 8H2O. The new mineral is orthorhombic, and the space group is Ibca. The unit-cell dimensions are: a = 11.7119, b = 19.973, c = 11.5652 A, and V = 2299.0 A3. The strongest reflections in the X-ray powder pattern [d, A (I, %)(hkl)] are: 5.001(30)(211), 4.788(42)(022), 3.847(89)(231), 2.932(42)(400), 2.832(35)(060), 2.800(97)(332, 233), and 2.774(100)(341, 143, 114). The crystal structure was studied using the Rietveld method, Rp = 5.77, Rwp = 7.77, RB = 2.07, and RF = 1.74. The structure is composed of isolated [SiO2(OH)2] octahedrons and the chains of edge-shared [Na[H2O)6] octahedrons. The Si and Na polyhedrons are linked only by H-bonds, and this is the cause of the low stability of chesnokovite under atmospheric conditions. The new mineral is named in memory of B.V. Chesnokov (1928–2005), an outstanding mineralogist. The type material of chesnokovite is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow.

Powder x-ray diffraction data of yttria (Y2O3) were obtained from room temperature to melting point with the thin wire resistance heating technique. A solid-state phase transition was observed at 2512 ± 25 K and melting of the high-uemperature phase at 2705 ± 25 K. Thermal expansion data for α–Y2O3 (C-type) are given for the range 298–2540 K. The unit cell parameter increases nonlinearly, especially just before the solid-state transition. The x-ray diffraction spectrum of the high-temperature phase is consistent with the fluorite-type structure (space group Fm3) with a refined unit cell parameter a = 5.3903(6) Å at 2530 K. The sample recrystallized rapidly above 2540 K, and above 2730 K, all the diffraction lines and spots disappeared from the x-ray diffraction spectrum that suggests complete melting.

Solid-State Synthesis, X-Ray Powder Diffraction, and IR Data of Na 2GdOPO 4

A new mineral, zvyaginite, a member of the epistolite group, has been found at Mt. Malyi Punkaruaiv, Lovozero Alkaline Complex, Kola Peninsula, Russia. It occurs in a hydrothermally altered peralkaline pegmatite and is associated with ussingite, microcline, aegirine, sphalerite, vigrishinite, and sauconite. Zvyaginite forms rectangular or irregular-shaped lamellae up to 0.1 × 1 × 2 cm in size when flattened [001]. The mineral is translucent to transparent and colorless, pearly-white, yellowish brownish, pale pink, or violet pink. The luster is nacreous on crystal faces and greasy on broken surfaces. Its Mohs’ hardness is 2.5–3. Zvyaginite is brittle. The cleavage parallel to {001} is perfect. Dmeas = 2.88(3), Dcalc = 2.94 g/cm3. The mineral is optically biaxial (−), α = 1.626(5), β = 1.714(3), γ = 1.740(5), 2Vmeas = 45(15)°, 2Vcalc = 55°. The IR spectrum is given. Chemical composition is as follows (wt %; average of five point analyses; H2O was determined using the modified Penfield method): 4.74 Na2O, 0.22 K2O, 0.77 CaO, 1.36 MnO, 0.24 FeO, 9.61 ZnO, 0.19 Al2O3, 29.42 SiO2, 12.33 TiO2, 27.22 Nb2O5, 1.94 F, 12.65 H2O, −0.82 −O = F2, for a total of 99.87. The empirical formula calculated on the basis of Si + Al = 4 is: Na1.24K0.04Ca0.11Mn0.16Fe0.03Zn0.96Nb1.66Ti1.25(Si3.97Al0.03)Σ4O15.07(OH)2.10F0.83(H2O)4.64. The simplified formula is: NaZnNb2Ti[Si2O7]2O(OH,F)3(H2O)4 + x (x < 1), Zvyaginite is triclinic, \(P\bar 1\), a = 8.975(3), b = 8.979(3), c = 12.135(4) A, α = 74.328(9)°, β = 80.651(8)°, γ = 73.959(8)°, V = 900.8(6) A3, Z = 2. The strongest reflections in the X-ray powder pattern (d, A-I[hkl]) are: 11.72–100[001], 5.83–40[002], 5.28–53[−1–11, 112], 4.289–86[200, 021], 3.896–36[−1–12, −201, 003, 022, 113], 2.916–57[310, 132, 004], 2.862–72[130, 312]. The model of the crystal structure was obtained on a single crystal, R = 0.159. Zvyaginite and epistolite are similar in the structure of the NbTiSiO motif, but differ from each other in composition of O layer in HOH block. Zvyaginite is named in honor of Boris B. Zvyagin (1921–2002), Russian crystallographer, crystal chemist and physicist. The type specimen is deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow.

The X-ray powder diffraction pattern for a new precursor in the synthesis of pyridyl tetrahydroquinolines was determined. 4-N-(4-methylphenyl)amine-4-(3′-pyridyl)-1-butene is monoclinic with refined unit cell parameters a=16.554(5), b=7.204(2), c=12.257(3) Å, β=99.76(2)°, V=1440.5(4) Å3, Z=4, and Dx=1.098 g/cm3, with space group P21/n (No. 14).

Synthesis, electrical properties, and conduction mechanism of [N(CH3)4]2PdCl4 compound

In this study, SrBAsO5 was synthesized by a solid state reaction using SrCO3, As2O5, and H3BO3 as reported before. The x-ray powder diffraction, FTIR, and Raman data were in agreement with the reported crystal structure. It crystallizes in a hexagonal system in P3121, and the refined unit cell parameters are a = 7.056(3) A, c = 6.898(1) A, and Z = 3. It is isostructural with SrBPO5. FTIR and Raman investigation of this compound were done for the first time in this study.

ABSTRACTZirconolites, CaZrTi2O7, from Sri Lanka and Pala Bora, South Africa, and a calzirtite, CaZr3 TiO9, from Jacupiranga, Brazil, were examined using the electron microprobe, x-ray diffraction (annealing study), transmission electron microscopy, scanning electron microscopy and optical microscopy. The x-ray data indicate that all three zirconolites are metamict. Both Sri Lanka zirconolites are amorphous to the limits of resolution of the electron microscope (֮10 A). The Pala Bora zirconolite is largely amorphous but contains isolated domains (50–200 A) of crystalline material which may be the result of post—metamict recrystallization and alteration. The only other significant evidence for chemical alteration was the lower Th concentration (1–2 weight percent) and slightly lower analytic totals for the rims of the Sri Lanka zirconolites. Upon annealing at 1130°C for 5 hours, all three zirconolites recrystallized as microcrystalline aggregates. Refined unit cell parameters and volumes are consistent with published data for synthetic zirconolites. Both Sri Lanka zirconolites contain microvoids, spherical in shape, and 200 Angstroms to 2 microns in size. This porosity may be the result of helium accumulation arising from the decay of U and Th. The calzirtite was highly crystalline, exhibited no porosity, and was unchanged by the annealing treatment.

The framework topology of zeolite MCM-22

Crystalline porous materials with large or extralarge pores continue to be of particular significance in both industry and academia for their potential applications in shape-selective catalysis and adsorption/separation. Of these zeolitic materials, especially aluminosilicateand aluminophosphate-based molecular sieves are of prime interest because of their high stability associated with their widespread use in many established process and emerging applications. The materials VPI-5 (VFI framework type, 18-ring) and UTD-1 (DON framework type, 14-ring) were the first extra-large pore (pores constructed of more than 12 Tatoms) aluminophosphate and aluminosilicate materials discovered. The oxide frameworks are built up by corner-sharing [AlO4] and [PO4] tetrahedra as well as [AlO4] and [SiO4] tetrahedra. In the search for materials with even larger pores, an anionic open-framework aluminophosphate JDF-20 (20-ring) was reported; however, it could not be classified as a zeolite because its framework (with an Al/P ratio of 5:6) is unstable upon removal of the occluded protonated templates by calcination. Larger pore openings were also achieved using Ge or Ga as the framework Tatom in a high amount, for example in ECR-34 (ETR framework type, 18-ring), ITQ-33 (18-ring), cloverite (-CLO framework type, 20ring), and ITQ-37 (30-ring). In this context, the use of Ge or Ga as framework atoms as well as fluoride has been found to facilitate the formation of a double four-ring (D4R) unit. This is in agreement with the prediction by Brunner and Meier that structures with extra-large pores should contain a large number of threeand four-membered rings. Ionothermal synthesis, in which ionic liquids act as both the solvent and template, is a novel method that has attracted great interest in the synthesis of zeolitic and other porous materials. Besides the advantage of experimenting at ambient pressure, ionic liquids offer different chemistry and structural variety associated with the use of additional amines as structure-directing agents (SDA), and therefore open up new vistas for the synthesis of new porous materials. Herein, we report the ionothermal synthesis of the first aluminophosphate molecular sieve with 20-ring pore openings, denoted as DNL-1 (Dalian National Laboratory Number 1). This molecular sieve was confirmed as a structural analogue to the gallophosphate molecular sieve cloverite by using a combination of Rietveld refinement of powder X-ray diffraction (PXRD) data and NMR analysis. Moreover, in comparison to cloverite, DNL-1, as-synthesized and calcined, exhibits excellent stability. DNL-1 was synthesized in the ionic liquid 1-ethyl-3methylimidazolate bromide ([emim]Br) with 1,6-hexanediamine (HDA) as the co-SDA. The detailed synthetic procedure is described in the Experimental Section. The assynthesized DNL-1 material displays uniformly globular agglomerates of grainlike nanocrystals with a diameter of about 20 mm (see the Supporting Information). Analysis by energy dispersive X-ray spectroscopy (EDX) indicates the P/ Al/F molar ratio of approximately 3:3:1. The inductively coupled plasma (ICP) analysis gives the content (wt%) of Al 16.50 and P 16.65. The elemental and thermogravimetric (TG) analyses show the content (wt%) of C 9.72, N 3.64, H 3.29, and a total weight loss of 34%. Combined with the results of the structure refinement (see below), the chemical formula of DNL-1 was determined as j (C6N2H18)104(C6N2H11)80(H2O)910 j [Al768P768O2976(OH)192F288]. Using the initial structure model from cloverite, the Rietveld refinement of as-synthesized DNL-1 was successfully performed in space group Fm 3c with refined unit cell parameter a= 51.363(1) , which is comparable to that of cloverite a= 51.713 , considering the smaller ionic radius of Al. Similar results were observed in the all-silica and Gecontaining polymorph C of zeolite Beta. Figure 1 shows the very good agreement between observed and calculated PXRDpatterns, taking into account the limited signal to noise ratio, in particular for the data collected at a high angle which can be reflected from the expected R factor of 14.5%. These results adequately confirm that DNL-1 is a pure aluminophosphate analogue of the -CLO structure. The skeletal model of the refined framework structure is shown in Figure 2. The framework of DNL-1 shows the general features of the -CLO structure: 1) two nonintersecting three-dimensional channel systems with 20-ring and 8-ring windows, respectively, 2) four terminal hydroxy groups (Al [*] Y. Wei, Prof. Z. Tian, R. Xu, Dr. H. Ma, R. Pei, Prof. W. Zhang, Prof. Y. Xu, Dr. L. Wang, K. Li, Dr. B. Wang, G. Wen, Prof. L. Lin State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences, Dalian 116023 (China) Fax: (+86)411-843-79151 E-mail: tianz@dicp.ac.cn

The structure type of La2Ti10.27Ga9.63O38 was revealed by a search-match using the PDF. A successful Rietveld refinement (Rp=8.9, Rwp=13.3, RB=4.20) confirmed the structure to be rhombohedral (space group R3¯, No. 148) with the refined unit cell parameters a=9.1878(1) Å, α=68.458(1)°, and V=646.374(1) Å3. The structure is compared to other compounds of the davidite type, and the observed and calculated powder data are given.

SrBPO5 was synthesized by a solid-state reaction reported and by a new solid state reaction using BPO4 as a phosphating agent. It was also obtained by a hydrothermal method. The structure of the compound was solved by Rietveld analysis before. The examination of X-ray powder diffraction data showed that, SrBPO5 is isostructural with CaBPO5 and BaBPO5. It crystallizes in the trigonal system in P3121 and the refined unit cell parameters are a = 6.8488(1), c = 6.8159(2) Å, Z=3 and Dm 3.77 g/cm3.