Abstract
The crystal chemistry of six natural datolites from different localities was investigated by electron microprobe analysis in the wavelength dispersive mode and single-crystal X-ray diffraction. The chemical analyses show no significant site substitution. The single-crystal structure refinements confirm the structural model of datolite previously reported (with a ~ 4.83, b ~ 7.61, c ~ 9.63 Å, and β ~ 90.15°, space group P21/c). Intra-polyhedral bond distances and angles show common features in all samples at room T: (1) the Si-tetrahedron is strongly deformed, with Si-O distances ranging between ~1.57 and ~1.66 Å and O-Si-O angles ranging between ~105.4 and ~115.3°; (2) the B-tetrahedron is almost regular; (3) the Ca-polyhedron is significantly distorted, with bond distances ranging between ~2.28 and ~2.67 Å; (4) only one independent H-site occurs and its refined position suggests a bifurcated hydrogen bonding scheme with O5 as donor and O4 and O2 as acceptors [with O5-H ~ 0.8 Å and (1) O5···O4 ~ 2.99 Å, H···O4 ~ 2.33 Å, and O5-H···O4 ~ 140°, and (2) O5···O2 ~ 2.96 Å, H···O2 ~ 2.36 Å, and O5-H···O2 ~ 131°]. Low-temperature diffraction measurements between 300 and 100 K show that the thermal expansion of datolite is mainly governed by the axial response along [100] and [010], whereas the c-axis length is almost unchanged in this temperature interval. The volume thermal expansion coefficient (αV = V-1∂V/∂T) between 100 and 280 K is αV = 1.5(2)·10-5 K-1. The higher thermal expansion of the a-axis is due to the layered nature of the structure of datolite: the Ca-O bond distances are the most compressible and expandable, and govern the contraction, upon cooling, along the direction perpendicular to the polyhedral layers. The tetrahedral layer is significantly more rigid and no changes of the tetrahedral tilts are observed from 300 to 100 K.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Ti-Al zoning of experimentally grown titanite in the system CaO-Al2O3-TiO2-SiO2-NaCl-H2O-(F): Evidence for small-scale fluid heterogeneity
- A new method for quantitative petrography based on image processing of chemical element maps: Part I. Mineral mapping applied to compacted bentonites
- A new method for quantitative petrography based on image processing of chemical element maps: Part II. Semi-quantitative porosity maps superimposed on mineral maps
- Enhancement of solid-state reaction rates by non-hydrostatic stress effects on polycrystalline diffusion kinetics
- (H3O)Fe(SO4)2 formed by dehydrating rhomboclase and its potential existence on Mars
- Crystal chemistry and low-temperature behavior of datolite: A single-crystal X-ray diffraction study
- Density and seismic velocities of chromitite body in oceanic mantle peridotite
- Packing schemes of cavities in selected clathrasils and zeolites and the analogous packings of atoms in crystal structures
- Temperature dependence of IR absorption of OH species in clinopyroxene
- Thermal behavior of vibrational phonons and hydroxyls of muscovite in dehydroxylation: In situ high-temperature infrared spectroscopic investigations
- Kinetics of Fe-oxidation/deprotonation process in Fe-rich phlogopite under isothermal conditions
- On the crystal chemistry of londonite [(Cs,K,Rb)Al4Be5B11O28]: A single-crystal neutron diffraction study at 300 and 20 K
- High-pressure melting of wüstite
- Primary Nb-Ta minerals in the Szklary pegmatite, Poland: New insights into controls of crystal chemistry and crystallization sequences
- Evolution of the interlayer space of hydrated montmorillonite as a function of temperature
- Morphology of pyrite in particulate matter from shallow submarine hydrothermal vents
- Influence of the fluid composition on diamond dissolution forms in carbonate melts
- Far infrared spectroscopy of carbonate minerals
- Assessment of the diamond-trap method for studying high-pressure fluids and melts and an improved freezing stage design for laser ablation ICP-MS analysis
- Françoisite-(Ce), a new mineral species from La Creusaz uranium deposit (Valais, Switzerland) and from Radium Ridge (Flinders Ranges, South Australia): Description and genesis
- Crystal chemistry and origin of grandidierite, ominelite, boralsilite, and werdingite from the Bory Granulite Massif, Czech Republic
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: III. Thorneite, Pb6(Te26+O10)(CO3)Cl2(H2O), the first mineral with edge-sharing octahedral tellurate dimers
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: IV. Markcooperite, Pb(UO2)Te6+O6, the first natural uranyl tellurate
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: V. Timroseite, Pb2Cu52+(Te6+O6)2(OH)2, and paratimroseite, Pb2Cu42+(Te6+O6)2(H2O)2, two new tellurates with Te-Cu polyhedral sheets
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: VI. Telluroperite, Pb3Te4+O4Cl2, the Te analog of perite and nadorite
- The determination of sulfate and sulfide species in hydrous silicate glasses using Raman spectroscopy
- The structure of crystals, glasses, and melts along the CaO-Al2O3 join: Results from Raman, Al L- and K-edge X-ray absorption, and 27Al NMR spectroscopy
- Ordering of iron vacancies in monoclinic jarosites
Articles in the same Issue
- Ti-Al zoning of experimentally grown titanite in the system CaO-Al2O3-TiO2-SiO2-NaCl-H2O-(F): Evidence for small-scale fluid heterogeneity
- A new method for quantitative petrography based on image processing of chemical element maps: Part I. Mineral mapping applied to compacted bentonites
- A new method for quantitative petrography based on image processing of chemical element maps: Part II. Semi-quantitative porosity maps superimposed on mineral maps
- Enhancement of solid-state reaction rates by non-hydrostatic stress effects on polycrystalline diffusion kinetics
- (H3O)Fe(SO4)2 formed by dehydrating rhomboclase and its potential existence on Mars
- Crystal chemistry and low-temperature behavior of datolite: A single-crystal X-ray diffraction study
- Density and seismic velocities of chromitite body in oceanic mantle peridotite
- Packing schemes of cavities in selected clathrasils and zeolites and the analogous packings of atoms in crystal structures
- Temperature dependence of IR absorption of OH species in clinopyroxene
- Thermal behavior of vibrational phonons and hydroxyls of muscovite in dehydroxylation: In situ high-temperature infrared spectroscopic investigations
- Kinetics of Fe-oxidation/deprotonation process in Fe-rich phlogopite under isothermal conditions
- On the crystal chemistry of londonite [(Cs,K,Rb)Al4Be5B11O28]: A single-crystal neutron diffraction study at 300 and 20 K
- High-pressure melting of wüstite
- Primary Nb-Ta minerals in the Szklary pegmatite, Poland: New insights into controls of crystal chemistry and crystallization sequences
- Evolution of the interlayer space of hydrated montmorillonite as a function of temperature
- Morphology of pyrite in particulate matter from shallow submarine hydrothermal vents
- Influence of the fluid composition on diamond dissolution forms in carbonate melts
- Far infrared spectroscopy of carbonate minerals
- Assessment of the diamond-trap method for studying high-pressure fluids and melts and an improved freezing stage design for laser ablation ICP-MS analysis
- Françoisite-(Ce), a new mineral species from La Creusaz uranium deposit (Valais, Switzerland) and from Radium Ridge (Flinders Ranges, South Australia): Description and genesis
- Crystal chemistry and origin of grandidierite, ominelite, boralsilite, and werdingite from the Bory Granulite Massif, Czech Republic
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: III. Thorneite, Pb6(Te26+O10)(CO3)Cl2(H2O), the first mineral with edge-sharing octahedral tellurate dimers
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: IV. Markcooperite, Pb(UO2)Te6+O6, the first natural uranyl tellurate
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: V. Timroseite, Pb2Cu52+(Te6+O6)2(OH)2, and paratimroseite, Pb2Cu42+(Te6+O6)2(H2O)2, two new tellurates with Te-Cu polyhedral sheets
- Lead-tellurium oxysalts from Otto Mountain near Baker, California: VI. Telluroperite, Pb3Te4+O4Cl2, the Te analog of perite and nadorite
- The determination of sulfate and sulfide species in hydrous silicate glasses using Raman spectroscopy
- The structure of crystals, glasses, and melts along the CaO-Al2O3 join: Results from Raman, Al L- and K-edge X-ray absorption, and 27Al NMR spectroscopy
- Ordering of iron vacancies in monoclinic jarosites