scholarly journals Kyawthuite, Bi3+Sb5+O4, a new gem mineral from Mogok, Burma (Myanmar)

2017 ◽  
Vol 81 (3) ◽  
pp. 477-484 ◽  
Author(s):  
Anthony R. Kampf ◽  
George R. Rossman ◽  
Chi Ma ◽  
Peter A. Williams
Keyword(s):  
Monoclinic Space Group ◽  
Optical Orientation ◽  
X Ray Diffraction ◽  
Calculated Density ◽  
Electron Pairs ◽  
X Ray ◽  
Conchoidal Fracture ◽  
Cell Dimensions ◽  
Mohs Hardness ◽  
Unit Cell Dimensions

AbstractKyawthuite, Bi3+Sb5+O4, is a new gem mineral found as a waterworn crystal in alluvium at Chaung-gyi-ah-le-ywa in the Chaung-gyi valley, near Mogok, Burma (Myanmar). Its description is based upon a single sample, which was faceted into a 1.61-carat gem.The composition suggests that the mineral formed in a pegmatite. Kyawthuite is monoclinic, space group I2/c, with unit cell dimensions a = 5.4624(4), b = 4.88519(17), c = 11.8520(8) Å, β = 101.195(7)°, V = 310.25(3) Å3and Z = 4. The colour is reddish orange and the streak is white. It is transparent with adamantine lustre. The Mohs hardness is 5½. Kyawthuite is brittle with a conchoidal fracture and three cleavages: {001} perfect, {110} and {110} good. The measured density is 8.256(5) g cm–3and the calculated density is 8.127 g cm–3. The mineral is optically biaxial with 2V = 90(2)°. The predicted indices of refraction are α = 2.194, β = 2.268, γ = 2.350. Pleochroism is imperceptible and the optical orientation is X = b; Y≈ c; Z ≈ a. Electron microprobe analyses, provided the empirical formula (Bi0.823+Sb0.183+)∑1.00(Sb0.995+Ta0.015+)∑1.00O4. The Raman spectrumis similar to that of synthetic Bi3+Sb5+O4. The infrared spectrum shows a trace amount of OH/H2O. The eight strongest powder X-ray diffraction lines are [dobs in Å(I)(hkl)]: 3.266(100)(112), 2.900(66)(112), 2.678(24)(200), 2.437(22)(020,114), 1.8663(21)(024), 1.8026(43)(116,220,204), 1.6264(23)(224,116) and 1.5288(28)(312,132). In the crystal structure of kyawthuite (R1 = 0.0269 for 593 reflections with Fo > 4σF), Sb5+O6 octahedrashare corners to form chequerboard-like sheets parallel to {001}. Atoms of Bi3+, located above and below the open squares in the sheets, form bonds to the O atoms in the sheets, thereby linking adjacent sheets into a framework. The Bi3+ atom is in lopsided 8 coordination,typical of a cation with stereoactive lone electron pairs. Kyawthuite is isostructural with synthetic β-Sb2O4 and clinocervantite (natural β-Sb2O4).

Hingganite-(Nd), Nd2□Be2Si2O8(OH)2, a new gadolinite-supergroup mineral from Zagi Mountain, Pakistan

2020 ◽  
Vol 58 (5) ◽  
pp. 549-562
Author(s):  
Anatoly V. Kasatkin ◽  
Fabrizio Nestola ◽  
Radek Škoda ◽  
Nikita V. Chukanov ◽  
Atali A. Agakhanov ◽  
...  
Keyword(s):  
New Mineral ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Average Chemical Composition ◽  
X Ray ◽  
Conchoidal Fracture ◽  
Icp Ms ◽  
Optical Axes ◽  
Mohs Hardness ◽  
Khyber Pakhtunkhwa Province

ABSTRACT Hingganite-(Nd), ideally Nd2□Be2Si2O8(OH)2, is a new gadolinite group, gadolinite supergroup mineral discovered at Zagi Mountain, near Kafoor Dheri, about 4 km S of Warsak and 30 km NW of Peshawar, Khyber Pakhtunkhwa Province, Pakistan. The new mineral forms zones measuring up to 1 × 1 mm2 in loose prismatic crystals up to 0.7 cm long, where it is intergrown with hingganite-(Y). Other associated minerals include aegirine, microcline, fergusonite-(Y), and zircon. Hingganite-(Nd) is dark greenish-brown, transparent, has vitreous luster and a white streak. It is brittle and has a conchoidal fracture. No cleavage or parting are observed. Mohs hardness is 5½–6. Dcalc. = 4.690 g/cm3. Hingganite-(Nd) is non-pleochroic, optically biaxial (+), α = 1.746(5), β = 1.766(5), γ = 1.792(6) (589 nm). 2Vmeas. = 80(7)°; 2Vcalc. = 84°. Dispersion of optical axes was not observed. The average chemical composition of hingganite-(Nd) is as follows (wt.%; electron microprobe, BeO, B2O3, and Lu2O3 content measured by LA-ICP-MS; H2O calculated by stoichiometry): BeO 9.64, CaO 0.45, MnO 0.10, FeO 3.03, B2O3 0.42, Y2O3 8.75, La2O3 1.63, Ce2O3 12.89, Pr2O3 3.09, Nd2O3 16.90, Sm2O3 5.97, Eu2O3 1.08, Gd2O3 5.15, Tb2O3 0.50, Dy2O3 2.50, Ho2O3 0.33, Er2O3 0.84, Tm2O3 0.10, Yb2O3 0.44, Lu2O3 0.04, ThO2 0.13, SiO2 23.55, H2O 2.72, total 100.25. The empirical formula calculated on the basis of 2 Si apfu is (Nd0.513Ce0.401Y0.395Sm0.175Gd0.145Pr0.096Dy0.068La0.051Ca0.041Eu0.031Er0.022Tb0.014Yb0.011Ho0.009Tm0.003Th0.003Lu0.001)Σ1.979(□0.778Fe2+0.215Mn0.007)Σ1.000(Be1.967B0.062)Σ2.029Si2O8.46(OH)1.54. Hingganite-(Nd) is monoclinic, space group P21/c with a = 4.77193(15), b = 7.6422(2), c = 9.9299(2) Å, β = 89.851(2)°, V = 362.123(14) Å3, and Z = 2. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 6.105 (95) (011), 4.959 (56) (002), 4.773 (100) (100), 3.462 (58) (102), 3.122 , 3.028 (61) (013), 2.864 (87) (121), 2.573 (89) (113). The crystal structure of hingganite-(Nd) was refined from single-crystal X-ray diffraction data to R = 0.034 for 2007 unique reflections with I > 2σ(I). The new mineral is named as an analogue of hingganite-(Y), hingganite-(Yb), and hingganite-(Ce), but with Nd dominant among the rare earth elements.

scholarly journals The reaction of 3,5-diphenyl-1,2-dithiolium-4-olate with aniline: the crystal structure of 1-phenylimino-2-phenylamino-3-phenylindene

1987 ◽  
Vol 65 (12) ◽  
pp. 2830-2833 ◽  
Author(s):  
David M. McKinnon ◽  
Peter D. Clark ◽  
Robert O. Martin ◽  
Louis T. J. Delbaere ◽  
J. Wilson Quail
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

3,5-Diphenyl-1,2-dithiolium-4-olate (1) reacts with aniline to form 1-phenylimino-2-phenylamino-3-phenylindene (3a). Under suitable conditions, 6-phenylbenzo[b]indeno[1,2-e]-1,2-thiazine is also formed. These structures are confirmed by alternative syntheses. The molecular structure of 3a has been determined by single crystal X-ray diffraction. Compound 3a crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 20.777(3) Å, b = 6.130(3) Å, c = 31.327(3) Å, 3 = 99.59(1)°, and Z = 8. The structure was solved by direct methods and refined by least squares to a final R = 0.055. The molecular structure of 3a shows the three phenyl containing substituents to have the planes of their ring systems tilted between 40° and 60° from the plane of the indene system due to steric repulsions.

Structures of 2 Vanadium(V) Complexes With Tridentate Ligands

1986 ◽  
Vol 39 (7) ◽  
pp. 1081 ◽  
Author(s):  
AA Diamantis ◽  
JM Frederiksen ◽  
MA Salam ◽  
MR Snow ◽  
ERT Tiekink
Keyword(s):  
Tridentate Ligand ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Tridentate Ligands ◽  
Tetragonal Pyramid ◽  
Coordination Environment ◽  
X Ray ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Oxo Ligand

The crystal structures of two vanadium(v) complexes, VOL(OCH2CH3)(1) and (VOL)2O (2), where L is the dinegative , tridentate ligand 4- phenylbutane-2,4-dione benzoylhydrazonato (2-), were determined by X-ray diffraction methods. Crystals of (1) are monoclinic, space group P21/n, a 11.064(4), b 7.565(1), c 21.786(5) Ǻ and β 95.93(2)° and Z 4; those of (2) are also monoclinic, C2/ c, with unit cell dimensions a 18.287(3), b 14.991(2), c 11.643(2)Ǻ, β 92.85(2)° for Z 4. The structures were refined by full-matrix least-squares methods to final R 0.036 for 1801 reflections with I ≥ 2.5σ(I) for (1), and R 0.061 for 1272 reflections with I ≥ 2.5σ(I) for (2). The coordination environment of the vanadium atom in both structures is a tetragonal pyramid with the oxo ligand occupying the apical positon.

Odigitriaite, CsNa5Ca5[Si14B2O38]F2, a new caesium borosilicate mineral from the Darai-Pioz alkaline massif, Tajikistan: Description and crystal structure

2017 ◽  
Vol 81 (1) ◽  
pp. 113-122 ◽  
Author(s):  
Atali A. Agakhanov ◽  
Leonid A. Pautov ◽  
Elena Sokolova ◽  
Frank C. Hawthorne ◽  
Vladimir Yu Karpenko ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Double Layer ◽  
Direct Methods ◽  
Double Layers ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Calculated Density ◽  
X Ray ◽  
Mohs Hardness ◽  
Alkaline Massif

AbstractOdigitriaite, a new Cs, Na, Ca borosilicate mineral, was discovered in moraine adjacent to the Darai-Pioz alkaline massif in the upper reaches of the Darai-Pioz river at the intersection of the Turkestansky, Zeravshansky and Alaisky mountain ridges, Tajikistan. It occurs as irregular thin flakes associated with quartz, pectolite, baratovite, fluorite, pekovite, polylithionite, aegirine, leucosphenite, pyrochlore, neptunite, reedmergnerite, mendeleevite-(Ce), zeravshanite and sokolovaite. It is colourless with a white streak, is translucent and has a vitreous lustre; it does not fluoresce under ultraviolet light. Odigitriaite is brittle with an uneven fracture and a Mohs hardness of 5. The calculated density is 2.80(2) g/cm3. The indices of refraction are α = 1.502, β = 1.564, γ = 1.576; 2Vobs = 46(2)°, dispersion is weak r > v, and there is no pleochroism. The chemical composition is as follows (electron microprobe, H2O calculated from structure): SiO2 55.30, Al2O3 0.09, Y2O3 0.44, MnO 0.94, FeO 0.10, PbO 0.21, K2O 0.01 Cs2O 8.36, B2O3 4.75, H2O 0.37, F 1.74, O = F2 –0.74, total 99.43 wt.%. The empirical formula of odigitriaite is Cs0.90Na5.12Ca4.68Mn0.20Y0.06Fe0.02Pb0.01[Si13.92Al0.03B2.06O38]F1.39(OH)0.62. The end-member formula is CsNa5Ca5[Si14B2O38]F2. The strong reflections in the powder X-ray diffraction pattern are: [(d, Å), (I, %), (hkl)]: 5.45 (25) (1 1 3), 4.66 (33) (3 1 1), 4.40 (26) (0 2 2), 4.10 (36) (3 1 3), 3.95 (25) (3̄ 1 3), 2.85 (31) (2 2 2), 2.68 (40) (0 0 6), 3.62 (45) (0 2 4), 3.35 (100) (2̄ 2 4), 3.31 (30) (3̄ 1 5), 3.25 (35) (4 0 4), 3.04 (60) (4̄ 2 2), 2.925 (22) (4̄ 2 3), 1.813 (23) (9 1 0). Odigitriaite is monoclinic, space group C2/c, a = 16.652(5), b = 9.598 (3), c = 22.120(7) Å, β= 92.875(14)°, V = 3530.9(1.9) Å3, Z = 4. The crystal structure of odigitriaite was solved by direct methods and refined to an R1 value of 2.75% based on single-crystal X-ray data. It is a double-layer sheet-borosilicate mineral; Cs and Na are intercalated within the double-layer sheet, and the double layers are linked by interstitial Ca and Na atoms.

Adanite, a new lead-tellurite-sulfate mineral from the North Star mine, Tintic, Utah, and Tombstone, Arizona, USA

2020 ◽  
Vol 58 (3) ◽  
pp. 403-410
Author(s):  
Anthony R. Kampf ◽  
Robert M. Housley ◽  
George R. Rossman ◽  
Hexiong Yang ◽  
Robert T. Downs
Keyword(s):  
Raman Spectrum ◽  
Powder Diffraction ◽  
Monoclinic Space Group ◽  
Calculated Density ◽  
X Ray ◽  
Conchoidal Fracture ◽  
The North ◽  
Cochise County ◽  
Mohs Hardness

ABSTRACT Adanite, Pb2(Te4+O3)(SO4), is a new oxidation-zone mineral from the North Star mine, Tintic district, Juab County, Utah, and from Tombstone, Cochise County, Arizona, USA. The characterization of the species is based principally on North-Star holotype material. Crystals are beige wedge-shaped blades, up to about 1 mm in length, in cockscomb intergrowths. The mineral is transparent with adamantine luster, white streak, Mohs hardness 2½, brittle tenacity, conchoidal fracture, and no cleavage. The calculated density is 6.385 g/cm3. Adanite is biaxial (–), with α = 1.90(1), β = 2.04(calc), γ = 2.08(calc), 2V(meas) = 54(1)°. The Raman spectrum is consistent with the presence of tellurite and sulfate groups and the absence of OH and H2O. Electron-microprobe analyses gave the empirical formula Pb1.89Sb3+0.02Te4+0.98S6+1.04Cl0.02O6.98. The mineral is monoclinic, space group P21/n, with a = 7.3830(3), b = 10.7545(5), c = 9.3517(7) Å, β = 111.500(8)°, V = 690.86(7) Å3, and Z = 4. The four strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 6.744(47), 3.454(80), 3.301(100), and 3.048(73). The structure (R1 = 0.022 for 1906 I > 2σI reflections) contains Te4+O3 pyramids that are joined by short (strong) Pb–O bonds to form sheets. Interlayer SO4 groups link the sheets via long Pb–O and Te–O bonds.

scholarly journals Lead-tellurium oxysalts from Otto Mountain near Baker, California, USA: XII. Andychristyite, PbCu2+Te6+O5(H2O), a new mineral with hcp stair-step layers

2016 ◽  
Vol 80 (6) ◽  
pp. 1055-1065 ◽  
Author(s):  
Anthony R. Kampf ◽  
Mark A. Cooper ◽  
Stuart J. Mills ◽  
Robert M. Housley ◽  
George R. Rossman
Keyword(s):  
Empirical Formula ◽  
New Mineral ◽  
X Ray Diffraction ◽  
Calculated Density ◽  
Quartz Veins ◽  
Bluish Green ◽  
Cell Dimensions ◽  
Perfect Cleavage ◽  
Mohs Hardness ◽  
Unit Cell Dimensions

AbstractAndychristyite, PbCu2+Te6+O5(H2O), is a new tellurate mineral from Otto Mountain near Baker, California, USA. It occurs in vugs in quartz in association with timroseite. It is interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of quartz veins. Andychristyite is triclinic, space group P1̄, with unit-cell dimensions a = 5.322(3), b = 7.098(4), c = 7.511 (4) Å, α = 83.486(7), β = 76.279(5), γ = 70.742(5)°, V = 260.0(2) Å3 and Z = 2. It forms as small tabular crystals up to ∼50 μm across, in sub-parallel aggregates. The colour is bluish green and the streak is very pale bluish green. Crystals are transparent with adamantine lustre. The Mohs hardness is estimated at between 2 and 3. Andychristyite is brittle with an irregular fracture and one perfect cleavage on {001}. The calculated density based on the empirical formula is 6.304 g/cm3. The mineral is optically biaxial, with large 2V, strong dispersion, and moderate very pale blue-green to medium blue-green pleochroism. The electron microprobe analyses (average of five) provided: PbO 43.21, CuO 15.38, TeO3 35.29, H2O 3.49 (structure), total 97.37 wt.%. The empirical formula (based on 6 O apfu) is: Pb0.98Cu2+0.98Te6+1.02O6H 1.96. The Raman spectrum exhibits prominent features consistent with the mineral being a tellurate, as well as an OH stretching feature confirming a hydrous component. The eight strongest powder X-ray diffraction lines are [dobs in Å(I)(hkl)]: 6.71(16)(010), 4.76(17)(110), 3.274(100)(120,102,012), 2.641(27)(102, 211, 112), 2.434(23)(multiple), 1.6736(17)(multiple), 1.5882(21)(multiple) and 1.5133(15)(multiple). The crystal structure of andychristyite (R1 = 0.0165 for 1511 reflections with Fo > 4σF) consists of stair-step-like hcp polyhedral layers of Te6+O6 and Cu2+O6 octahedra parallel to {001}, which are linked in the [001] direction by bonds to interlayer Pb atoms. The structures of eckhardite, bairdite, timroseite and paratimroseite also contain stair-step-like hcp polyhedral layers.

Crystal structure and crystal chemistry of fluoro-potassic-magnesio-arfvedsonite from Monte Metocha, Xixano region, Mozambique, and discussion of the holotype from Quebec, Canada

2010 ◽  
Vol 74 (6) ◽  
pp. 951-960 ◽  
Author(s):  
R. Oberti ◽  
M. Boiocchi ◽  
F. C. Hawthorne ◽  
P. Robinson
Keyword(s):  
Polarized Light ◽  
X Ray Diffraction ◽  
Calculated Density ◽  
Amphibole Composition ◽  
Fine Grained ◽  
Holotype Specimen ◽  
Cell Dimensions ◽  
Mohs Hardness ◽  
Crystallization Conditions ◽  
Unit Cell Dimensions

AbstractFluoro-potassic-magnesio-arfvedsonite, ideally AKBNa2c(Mg4Fe3+)TSi8O22wF2, has been found in a dyke ∼25 km southwest of Monte Metocha, Xixano region, northeastern Mozambique. Fluoro-potassic-magnesio-arfvedsonite and low sanidine form a fine-grained mafic, ultrapotassic, peralkaline igneous rock without visible phenocrysts. The amphibole is brittle, has a Mohs hardness of 6 and a splintery fracture; it is non-fluorescent with perfect {110} cleavage and no observable parting, and has a calculated density of 3.174 gcm−3. In plane-polarized light, it is pleochroic, X= pale grey-green, Y = blue-green, Z = pale grey; X ^ c = 23.6° (in β obtuse), Y ‖ b, Z ^ c = 66.4° (in β acute). Fluoro-potassic-magnesio-arfvedsonite is biaxial negative, α = 1.652(2), β = 1.658(2), γ = 1.660(2); 2Vobs = 22.5(7)°, 2Vcalc = 30.2°. The unit-cell dimensions are a = 9.9591(4), b = 17.9529(7), c = 5.2867(2) Å, β = 104.340(1)°, V = 919.73(10) Å3, Z = 2. The nine strongest X-ray diffraction lines in the experimental powder pattern are: [d in Å(I)(hkl)]: 2.716(100)(151), 3.410(70)(131), 8.475(50)(110), 3.178(50)(310), 3.309(30)(240), 2.762(20)(31), 2.549(20)(260), 2.351(10)(51), 2.269(10)(331). Electron microprobe analysis gave: SiO2 54.25, A12O3 0.03, TiO2 1.08, FeO 6.69, Fe2O3 8.07, MgO 13.99, MnO 0.32, ZnO 0.05, CaO 1.16, Na2O 6.33, K2O 5.20, F 2.20, H2Ocalc 0.74, sum 99.18 wt.%. The formula unit, calculated on the basis of 24 (O,OH,F) with (OH+F) = 2−(2 Ti), is AKa0.98B(Na1.18Ca0.18)∑1.99C(Mg3.07Fe0.832+Mn0.04Al0.01Fe0.903+Ti0.12Zn0.01)∑=4.98TSi8O22W[Fi.o3(OH)0.73O0.24]∑2.00 and confirms the usual pattern of cation order in the amphibole structure. The presence of a significant oxo component (locally balanced by Ti at the M(1) site) is related to the crystallization conditions. The presence of Fe3+ at the T sites, originally suggested for the holotype specimen, is discounted for this amphibole composition.

Penberthycroftite, [Al6(AsO4)3(OH)9(H2O)5]·8H2O, a second new hydrated aluminium arsenate mineral from the Penberthy Croft mine, St. Hilary, Cornwall, UK

2016 ◽  
Vol 80 (7) ◽  
pp. 1149-1160 ◽  
Author(s):  
I. E. Grey ◽  
J. Betterton ◽  
A. R. Kampf ◽  
C. M. Macrae ◽  
F. L. Shanks ◽  
...  
Keyword(s):  
Layer Structure ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Single Crystal Diffraction ◽  
Calculated Density ◽  
Metal Atoms ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Hydrated Aluminium ◽  
The Ideal

AbstractPenberthycroftite, ideally [Al6(AsO4)3(OH)9(H2O)5]·8H2O, is a new secondary aluminium arsenate mineral from the Penberthy Croft mine, St. Hilary, Cornwall, England, UK. It occurs as tufts of white, ultrathin (sub-micrometre) rectangular laths, with lateral dimensions generally < 20 μm. The laths are flattened on {010} and elongated on [100]. The mineral is associated with arsenopyrite, bettertonite, bulachite, cassiterite, chalcopyrite, chamosite, goethite, liskeardite, pharmacoalumite–pharmacosiderite and quartz. Penberthycroftite is translucent with a white streak and a vitreous to pearly lustre. The calculated density is 2.18 g/cm3. Optically, only the lower and upper refractive indices could be measured, 1.520(1) and 1.532(1) respectively. No pleochroism was observed. Electron microprobe analyses (average of 14) with H2O obtained from thermogravimetric analysis and analyses normalized to 100% gave Al2O3 = 31.3, Fe2O3 = 0.35, As2O5 = 34.1, SO3 = 2.15 and H2O = 32.1. The empirical formula, based on nine metal atoms and 26 framework anions is [Al5.96Fe0.04(As0.97Al0.03O4)3(SO4)0.26(OH)8.30(H2O)5.44](H2O)7.8, corresponding to the ideal formula [Al6(AsO4)3(OH)9(H2O)5]·8H2O. Penberthycroftite is monoclinic, space group P21/c with unit-cell dimensions (100 K): a = 7.753(2) Å, b = 24.679(5) Å, c = 15.679(3) Å and β = 94.19(3)°. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I) (hkl)] 13.264(46) (011); 12.402(16)(020); 9.732(100)(021); 7.420(28)(110); 5.670(8)(130); 5.423(6)(1̄31). The structure of penberthycroftite was solved using synchrotron single-crystal diffraction data and refined to wRobs = 0.059 for 1639 observed (I> 3σ(I)) reflections. Penberthycroftite has a heteropolyhedral layer structure, with the layers parallel to {010}. The layers are strongly undulating and their stacking produces large channels along [100] that are filled with water molecules. The layers are identical to those in bettertonite, but they are displaced relative to one another along [001] and [010] such that the interlayer volume is decreased markedly (by ∼10%)relative to that in bettertonite, with a corresponding reduction in the interlayer water content from 11 H2O per formula unit (pfu) in bettertonite to 8 H2O pfu in penberthycroftite.

scholarly journals The crystal structure of 1-(4-chlorophenyl)-3-(4-methylbenzoyl)thiourea

2005 ◽  
Vol 3 (4) ◽  
pp. 780-791 ◽  
Author(s):  
Aamer Saeed ◽  
Masood Parvez
Keyword(s):  
Crystal Structure ◽  
Monoclinic Space Group ◽  
Fragmentation Pattern ◽  
X Ray Diffraction ◽  
1H And 13C Nmr ◽  
X Ray ◽  
Cell Dimensions ◽  
Intramolecular Hydrogen ◽  
Unit Cell Dimensions ◽  
Strong Intramolecular Hydrogen Bond

Abstract1-(4-Chlorophenyl)-3-(4-methylbenzoyl)thiourea was synthesized and characterized by IR,1H and 13C NMR, mass spectroscopy and the elemental analysis. The crystal structure was confirmed from single crystal X-ray diffraction data. It crystallizes in the monoclinic space group P21/c with unit cell dimensions a=12.038(3), b=6.330(6), c=18.912(5) Å and β=100.32(3)°. There is a strong intramolecular hydrogen bond of the type N−H...O, with distance N1...O1=2.659(3) Å. The structure is composed of dimers related by inversion centers. The dimers are formed by intermolecular interactions of the type N−H...S with N...S separation of 3.440(2) Å. The mass fragmentation pattern has also been discussed.

Bettertonite, [Al6(AsO4)3(OH)9(H2O)5]·11H2O, a new mineral from the Penberthy Croft mine, St. Hilary, Cornwall, UK, with a structure based on polyoxometalate clusters

2015 ◽  
Vol 79 (7) ◽  
pp. 1849-1858 ◽  
Author(s):  
I.E. Grey ◽  
A.R. Kampf ◽  
J.R. Price ◽  
C.M. Macrae
Keyword(s):  
Layer Structure ◽  
New Mineral ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Calculated Density ◽  
Hexagonal Ring ◽  
Metal Atoms ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

AbstractBettertonite, ideally [Al6(AsO4)3(OH)9(H2O)5]·11H2O, is a new mineral from the Penberthy Croft mine, St. Hilary, Cornwall, England, UK. It occurs as tufts of white, ultrathin (sub-micrometre) rectangular laths, with lateral dimensions generally <20 μm. The laths are flattened on {010} and exhibit the forms {010}, {100} and {001}. The mineral is associated closely with arsenopyrite, chamosite, liskeardite, pharmacoalumite, pharmacosiderite and quartz. Bettertonite is translucent with a white streak and a vitreous to pearly, somewhat silky lustre. The calculated density is 2.02 g/cm3. Optically, bettertonite is biaxial positive with α = 1.511(1), β = 1.517(1), γ = 1.523(1) (in white light). The optical orientation is X = c, Y= b, Z = a. Pleochroism was not observed. Electron microprobe analyses (average of 4) with H2O calculated on structural grounds and analyses normalized to 100% gave Al2O3 = 29.5, Fe2O3 = 2.0, As2O5= 30.1, SO3 = 1.8, Cl = 0.5, H2O = 36.2. The empirical formula, based on 9 metal atoms is Al5.86Fe0.26(AsO4)2.65(SO4)0.23(OH)9.82Cl0.13(H2O)15.5. Bettertoniteis monoclinic, space group P21/c with unit-cell dimensions (100 K): a = 7.773(2), b = 26.991(5), c = 15.867(3) Å, β = 94.22(3)°. The strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I)(hkl)] 13.648(100)(011); 13.505(50) (020); 7.805(50)(031); 7.461(30)(110); 5.880(20)(130); 3.589(20)(02); 2.857(14)(182). The structure of bettertonite was solved and refined to R1 = 0.083 for 2164 observed (I > 2σ(I)) reflections to a resolutionof 1 Å. Bettertonite has a heteropolyhedral layer structure, with the layers parallel to (010). The layers are strongly undulating and their stacking produces large channels along [100] that are filled with water molecules. The basic building block in the layers is a hexagonal ring ofedge-shared octahedra with an AsO4 tetrahedron attached to one side of the ring by corner-sharing. These polyoxometalate clusters, of composition [AsAl6O11(OH)9(H2O)5]8–, are interconnected along [100] and [001]by corner-sharing with other AsO4 tetrahedra.

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