Single Crystal Quartz Research Articles

The Role of α−β Quartz Transition in Fluid Storage in Crust From the Evidence of Electrical Conductivity

AbstractAqueous fluids are extensively present in the middle to lower crust, as revealed by seismic and magnetotelluric soundings. The α−β quartz phase transition significantly affects many physical properties and leads to substantial microcracks that can provide pathways for the migration of crustal fluids. A systematic investigation of macroscopic physical properties and microstructure of quartz is crucial to elucidate their correlation. In the present study, the effects of water content, trace elements, orientations, and phase transition on the electrical conductivity of quartz were thoroughly evaluated at 400−900°C and 1 GPa. Individual annealing experiments were simultaneously conducted on quartz single crystals at different peak temperatures and 1 GPa to investigate the evolution and spatial distribution of microcracks using X‐ray microtomography (CT) and backscattered electron imaging. We found that trace element content and orientations, rather than H2O, are the dominant factors controlling the conductivity of quartz. The distinct changes in conductivity of single crystals at around α−β phase transition temperature are attributed to the transformation of microcracks from isolated to interconnected networks, as confirmed by two‐dimensional (2‐D) and three‐dimensional (3‐D) microstructure images. Based on the variation in electrical conductivity and microstructure across the transition, it thus is proposed that the intragranular microcracks caused by quartz phase transition can serve as fluid or melt pathways within highly conductive zones present in the middle to lower crust, while α‐quartz acts as an impermeable cap.

Versatile pressure and temperature controlled cell for neutron reflectometry and small-angle neutron scattering

We have designed and realized a temperature and pressure controlled cell for Neutron Reflectometry (NR) and Small Angle Neutron Scattering (SANS) that is compatible with simultaneous optical transmission and resistivity measurements. The cell can accommodate samples up to 102 mm (4 inch) in diameter, can be pressurized from vacuum up to 10 bar gas pressure and the sample temperature can be controlled up to 350°C. The four single crystal quartz windows ensure both a good neutron and optical transmission and hence can be used in combination with in-situ optical transmission measurements. We present the cell and illustrate its performance with a series of neutron reflectometry experiments performed on Ta based thin films under a hydrogen containing atmosphere.

Shock-induced dissociation of soda-lime glass and the formation of single crystals of quartz and polycrystalline silicon

Amorphous soda-lime glass was subjected to shock induced loading with velocities of the impactor ∼10 km/s. The recovered sample was analyzed using high resolution x-ray diffraction and cross-polarized microscopy. The recovered samples were in form of aggregate consisting of the crystalline phases, polycrystalline alpha quartz, and silicon, which were identified in x-ray diffraction scans. We demonstrate high velocity impacts result in the transformation of amorphous glass to single crystalline quartz as a alpha-phase, and shock induced dissociation of silica into Si. In addition, a trace amount of tetragonal stishovite phase, which is extremely hard high-pressure phase of silicon dioxide, has been observed. This provides a new insight in understanding materials transformation behavior under extreme conditions. This will also contribute to our understanding of astronomical phenomenon, including meteorite and asteroid impacts on Earth and Earth-like planets.

An experimental study of hydrogen implantation to minerals: Role of the solar wind as a source of water in terrestrial bodies

The solar wind is a possible source for hydrogen and other volatiles on planetary bodies. To better understand the role of the solar wind during the volatile acquisition of planetary materials, we conducted hydrogen implantation experiments on olivine, orthopyroxene, quartz single crystals. Depth profiles of hydrogen concentration after implantation are determined by the Nuclear Resonance Reaction Analysis. We find that energetic hydrogen particles penetrate into the sample and accumulate at a certain depth. The hydrogen concentration increases with the hydrogen fluence until a “saturation level” is attained. Hydrogen saturation level (e.g., ∼10–20 at.% in olivine, equivalent to 0.5–1.2 wt%) far exceeds the equilibrium solubility in the bulk crystal at a similar thermodynamic condition (∼10−22 wt%). The results of olivine show that the hydrogen penetration depth increases whereas the saturation level decreases (weakly) with the beam energy. Hydrogen saturation level also depends on the mineral species in the order: olivine > orthopyroxene > quartz. The experimental results can be applied to explain some observations on the high surface water content of some planetary bodies including Itokawa asteroid and the Moon. We also explore the possibility of hydrogenated dusts by the solar wind implantation as a source for water on terrestrial planets. We conclude that if all dusts were exposed to the solar wind and all implanted hydrogen were converted to water, then >10 ocean masses would have been acquired for Earth by ∼100 years. However, the main part of the proto-planetary disk was not exposed to the solar wind and dusts could have been hydrogenated only when they were far from the equatorial plane of the disk. We discuss a possible mechanism to transport the hydrogenated dusts to the disk interior via turbulent mixing. Also, our experimental results and the mass dependence of the particle energies in the solar wind suggest that the D/H ratio of the dusts exposed to the solar wind will be higher than the solar wind value.

A New Mechanism for Stishovite Formation During Rapid Compression of Quartz and Implications for Asteroid Impacts

AbstractShock‐induced transformations of quartz to high‐pressure polymorphs and diaplectic glass are decisive in identifying impact cratering events. Under shock compression, quartz can melt in local hot spots and crystallization of these silica melts under pressure can yield the high‐pressure mineral stishovite. A solid‐state transition to stishovite in relation to the formation of amorphous lamellae was already suggested in the late 1960s, but this idea was never comprehensively proven. Therefore, the mechanism responsible for such an intracrystalline stishovite formation is unknown to date. Herein, crystallographically oriented single crystals of quartz were compressed and decompressed in a membrane‐driven diamond anvil cell. These experiments aim at simulating the pressure paths of natural impacts on the timescale of seconds using compression rates between 0.2 and 0.6 GPa/s and peak pressures between 20 and 37 GPa. During the compression of quartz, the time‐resolved synchrotron X‐ray diffraction patterns reveal the almost simultaneous formation of two high‐pressure polymorphs, the recently identified rosiaite‐structured silica and stishovite. Transmission electron microscopic observations of recovered samples show that stishovite occurs as arrays of uniformly oriented nanometer‐sized crystals in amorphous intracrystalline lamellae. These observations indicate that the numerous stishovite crystals likely nucleated from the structurally similar rosiaite phase and thus inherited their uniform orientation during compression. During decompression, the metastable and non‐quenchable rosiaite‐structured phase collapsed to the amorphous stishovite‐containing lamellae. These findings attest to a novel mechanism of the formation of stishovite in the solid state and provide an explanation for similar microstructural occurrences of stishovite in impact‐metamorphic rocks and shocked meteorites.

Surface-Guided Crystallization of Xanthine Derivatives for Optical Metamaterial Applications.

Numerous bio-organisms employ template-assisted crystallization of molecular solids to yield crystal morphologies with unique optical properties that are difficult to reproduce synthetically. Here, a facile procedure is presented to deposit bio-inspired birefringent crystals of xanthine derivatives on a template of single-crystal quartz. Crystalline sheets that are several millimeters in length, several hundred micrometers in width, and 300-600nm thick, are obtained. The crystal sheets are characterized with a well-defined orientation both in and out of the substrate plane, giving rise to high optical anisotropy in the plane parallel to the quartz surface, with a refractive index difference Δn ≈ 0.25 and a refractive index along the slow axis of n ≈ 1.7. It is further shown that patterning of the crystalline stripes with a tailored periodic grating leads to a thin organic polarization-dependent diffractive meta-surface, opening the door to the fabrication of various optical devices from a platform of small-molecule based organic dielectric crystals.

Texture measurements on quartz single crystals to validate coordinate systems for neutron time-of-flight texture analysis

In crystallographic texture analysis, ensuring that sample directions are preserved from experiment to the resulting orientation distribution is crucial to obtain physical meaning from diffraction data. This work details a procedure to ensure instrument and sample coordinates are consistent when analyzing diffraction data with a Rietveld refinement using the texture analysis softwareMAUD. A quartz crystal is measured on the HIPPO diffractometer at Los Alamos National Laboratory for this purpose. The methods described here can be applied to any diffraction instrument measuring orientation distributions in polycrystalline materials.

ASSESSMENT OF CRYSTALLINITY DEGREE OF QUARTZ RAW MATERIALS

Link for citation: Korovkin M.V., Ananyeva L.G., Zherlitsyn A.A., Kondratiev S.S., Savinova O.V., Kurskaya V.S. Assessment of crystallinity degree of quartz raw materials. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 8, рр. 59-67. In Rus. The relevance of research is determined by the need to assess the degree of transformation of quartz raw materials in its natural occurrence, as well as, changes in the properties of raw materials and products are exploited under various operating conditions. X-ray diffraction and Infrared spectroscopy was used to assess the degree of crystallinity of various crystalline quartz materials and products made of silicon dioxide, which showed satisfactory convergence of results and can be recommended for use in world practice. Objects: artificially grown quartz, including samples of synthetic quartz with an admixture of aluminum, zone-colored single crystal of quartz with an admixture of two and ferric iron; natural crystals of amethyst, smoky quartz, optical quartz; samples of fused quartz, products made of technical and optical quartz and silicate glass; as well as fine-grained samples of quartzites, including their micro- and nano-sized fractions. Methods: optical and electron scanning microscopy, X-ray spectral and analysis, infrared spectroscopy, X-ray diffraction. Results. The paper shows that the degree of crystallinity of quartz raw materials and products based on it is determined by the presence of a structural ordering in the near zone that characterizes the crystalline state corresponding to the a-quartz phase, which is confidently recorded by XRD and FTIR methods. The local disorder of high-purity quartz or quartzites having various impurities or defects in their structure that arise under the influence of external influences or exploitation causes deterioration of their properties and decrease in the degree of crystallinity.

Hydrothermal alkaline synthesis and release properties of silicon compound fertiliser using high-ash coal slime.

High-ash coal slime is difficult to utilise as a boiler fuel, and its accumulation results in environmental pollution. In this study, we describe a new method for the preparation of high-ash coal slime silica compound fertiliser (HASF) using CaO-KOH mixed hydrothermal method to optimize the utilization of this industrial waste and relieve the pressure on the fertiliser industry. The coal slime (D0) used in this study and its dry basis ash content by 1mol/L and 4mol/L sulfuric acid pre-activation (D1, D4) were greater than 85%. The effective silicon content of D0, D1, and D4 silica compound fertilisers reached 30.24%, 31.24%, and 17.35%, respectively, and the sums of effective silica-calcium-potassium oxides were 57.28%, 58.87%, and 48.16%, respectively, under the optimal reaction conditions of 230°C, 15h, and 1mol/L KOH, which met the market requirements, as determined using single-factor experiments. We used XRD, FTIR, and SEM-EDS analysis techniques to demonstrate that tobermorite and leucite were the main mineral phases of the compound fertiliser, and activated coal slime D4, which contains only quartz single crystals, required more demanding reaction conditions in the synthesis reaction. Subsequently, the cumulative release pattern of HASF silica was well described by the power function equation via repeated extraction and dissolution experiments, with the dissolution rate following D4 > D1 ≈ D0. Furthermore, 4mol/L sulfuric acid pre-activation resulted in the enrichment of HASF combined with organic matter and increased the slow-release rate of HASF silica. Thus, the synthesized HASF could have potential application prospects in soil improvement and fertilisation.

Evidence for a rosiaite-structured high-pressure silica phase and its relation to lamellar amorphization in quartz

When affected by impact, quartz (SiO2) undergoes an abrupt transformation to glass lamellae, the planar deformation features (PDFs). This shock effect is the most reliable indicator of impacts and is decisive in identifying catastrophic collisions in the Earth´s record such as the Chicxulub impact. Despite the significance of PDFs, there is still no consensus how they form. Here, we present time-resolved in-situ synchroton X-ray diffraction data of single-crystal quartz rapidly compressed in a dynamic diamond anvil cell. These experiments provide evidence for the transformation of quartz at pressures above 15 GPa to lamellae of a metastable rosiaite (PbSb2O6)-type high-pressure phase with octahedrally coordinated silicon. This phase collapses during decompression to amorphous lamellae, which closely resemble PDFs in naturally shocked quartz. The identification of rosiaite-structured silica provides thus an explanation for lamellar amorphization of quartz. Furthermore, it suggests that the mixed phase region of the Hugoniot curve may be related to the progressive formation of rosiaite-structured silica.

Backstresses in geologic materials quantified by nanoindentation load-drop experiments

ABSTRACT Transient creep of geologic materials is inferred to control many large-scale phenomena such as post-seismic deformation and post-glacial isostatic readjustment. Viscoelastic simulations can reproduce transient creep measured at Earth’s surface via GPS, but these approaches are entirely phenomenological, lacking a microphysical basis. This empirical nature limits our ability to extrapolate to future events and longer time scales. Recent experimental work has identified the importance of strain hardening and backstresses among dislocations in the transient deformation of geologic materials at both high and low temperatures, but very few experimental measurements of such backstresses exist. Here, we develop a nanoindentation load-drop method that can measure the magnitude of backstresses in a material. Using this method and a self-similar Berkovich tip, we measure backstresses in single crystals of olivine, quartz, and plagioclase feldspar at a range of indentation depths from 100–1750 nm, corresponding to geometrically necessary dislocation (GND) densities of order 1014–1015 m−2. Our results reveal a power-law relationship between backstress and GND density with an exponent ranging from 0.44–0.55 for each material, in close agreement with the theoretical prediction (0.5) from Taylor hardening. This work supports the assertion that backstresses and their evolution must be considered in future models of both transient and steady-state deformation in the Earth.

Comparing the monochromatic TL response of a high sensitivity natural quartz irradiated with β and γ rays

This study investigates the effect of the dose-rate in the thermoluminescent glow curves of a single crystal of quartz. The samples were sensitized by the γ radiation combined with the heat-treatments. The glow curves were registered in zeroed (unsensitized) and sensitized conditions using an optical filter centered in violet spectral region. Tens mGy test doses were administered with one β (90Sr/90Y) source and two γ radiation sources (60Co and 137Cs). The TL curves were deconvoluted using a first-order kinetic model. Differences in the glow curves and trapping parameters were observed between zeroed and sensitized samples. Differences were found in the TL curves comparing the three radiation sources. The principal variation is the remarkable increase in the TL signal above 350 °C, which is observed only in sensitized samples with the minor dose-rate source (137Cs). This signal seems to be associated with deep trapping states. The intensities of the components defining the first peak and the high temperature signal show a dependence on the dose-rate. The dose-rate dependence of the first-peak components is explained by the competing effects that may take place during the excitation stage. The components that fitted the sensitized peak (260 oC) do not exhibit a clear dependence on the dose-rate of radiation source.

Low-Frequency Magnetic Field Detection Using Magnetoelectric Sensor With Optimized Metglas Layers by Frequency Modulation

It is an important engineering challenge to detect a weak magnetic field <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${H}_{AC}$ </tex-math></inline-formula> at low frequencies (1-100 Hz) due to large noise. In this work, a magnetoelectric (ME) sensor using single-crystal quartz material as the piezoelectric phase and optimized magnetostrictive layers has been presented to sense the low-frequency magnetic field signals. Firstly, the ME response properties of the bulk Metglas/quartz/Metglas laminate sensor were studied and a high ME coefficient of 3038 V/(cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cdot $ </tex-math></inline-formula> Oe) has been attained in its electromechanical resonance frequency. With frequency modulation technique, which a magnetic low-frequency signal can be transferred to around resonance frequency of the sensor, the proposed sensor was used to detect the low frequency magnetic field signals under zero bias conditions. It is experimentally found that the absolute resolution with respect to a 1 Hz magnetic field can be decreased as low as 44 pT ± 1.41 pT with 20 layers of Metglas. More importantly, the ME coefficients with different layers under zero bias and the effect of Metglas layers on the limit of the detection at 1 Hz also have been investigated. The results show that the limit of the detection at 1 Hz can be decreased to 10 pT ± 0.32 pT with 14 layers of Metglas which indicates an enhancement by 4.4 times in comparison with 20 layers. This simple bulk Metglas/quartz/Metglas laminate sensor with optimized layers has a great potential to be used for low-frequency bio-magnetic signals measurement at room temperature.

Nanostructured Manganite Films Grown by Pulsed Injection MOCVD: Tuning Low- and High-Field Magnetoresistive Properties for Sensors Applications.

The results of colossal magnetoresistance (CMR) properties of La0.83Sr0.17Mn1.21O3 (LSMO) films grown by pulsed injection MOCVD technique onto various substrates are presented. The films with thicknesses of 360 nm and 60 nm grown on AT-cut single crystal quartz, polycrystalline Al2O3, and amorphous Si/SiO2 substrates were nanostructured with column-shaped crystallites spread perpendicular to the film plane. It was found that morphology, microstructure, and magnetoresistive properties of the films strongly depend on the substrate used. The low-field MR at low temperatures (25 K) showed twice higher values (−31% at 0.7 T) for LSMO/quartz in comparison to films grown on the other substrates (−15%). This value is high in comparison to results published in literature for manganite films prepared without additional insulating oxides. The high-field MR measured up to 20 T at 80 K was also the highest for LSMO/quartz films (−56%) and demonstrated the highest sensitivity S = 0.28 V/T at B = 0.25 T (voltage supply 2.5 V), which is promising for magnetic sensor applications. It was demonstrated that Mn excess Mn/(La + Sr) = 1.21 increases the metal-insulator transition temperature of the films up to 285 K, allowing the increase in the operation temperature of magnetic sensors up to 363 K. These results allow us to fabricate CMR sensors with predetermined parameters in a wide range of magnetic fields and temperatures.

Defect structure formation in quartz single crystal at the early stages of deformation

Accumulation of defects in the synthetic quartz single crystal has been investigated at the early stages of deformation. Process is studied with the help of three independent nondestructive techniques, namely: acoustic emission, X-ray computed tomography and synchrotron radiation topography. It is shown that results obtained by the three techniques are consistent with each other, allow detecting the area of defect formation and, what is more important, to match acoustic emission parameters with the ones of defects. This result is of practical importance, since it makes it possible to further identify areas of fracture growth and estimate their size in situ only by analyzing acoustic emission data in cases where the use of other control methods is impossible. Keywords: acoustic emission, X-ray computed tomography, synchrotron radiation topography (X-ray Diffraction Imaging), quartz single crystal, defects volume.

Investigation of local internal stresses under conditions of uniaxial compression of a quartz single crystal

Based on the analysis of the time intervals between acoustic emission signals obtained in the process of uniaxial compression of a cylindrical sample of a quartz single crystal, local stresses were estimated. It is shown that a decrease in the ability of a material to monotonic stress relaxation with time can serve as a signal for the imminent breakdown of the material. Keywords: acoustic emission, kinetic concept of strength, local mechanical stresses.

Формирование дефектной структуры монокристалла кварца на ранних этапах деформирования

Accumulation of defects in the synthetic quartz single crystal has been investigated at the early stages of deformation. Process is studied with the help of three independent nondestructive methods, namely: acoustic emission, X-ray computed tomography and synchrotron radiation topography. It is shown that results obtained by the three methods are consistent with each other, allow detecting the area of defect formation and, what is more important, to match acoustic emission parameters with the ones of defects. This result is of practical importance, since it makes it possible to further identify areas of fracture growth and estimate their size in situ only by analyzing acoustic emission data in cases where the use of other control methods is impossible.

Using ToF-SIMS analyses for analysing individual oil inclusions of different fluorescence colours in a single quartz crystal from the Barrandian (Czech Republic)

The fluorescence colour and molecular signature of oil inclusions can provide precious information on the thermal maturity of inclusion oils and the fluid migration history of basins. Here we show how molecular mass spectrometric analyses in combination with fluorescence microscopy can be used to reveal heterogeneities in the chemical compositions of oil inclusions within a micrometer sized quartz crystal. We used time-of-flight secondary ion mass spectrometry (ToF-SIMS) to extract and directly analyse the molecular content of two yellow and two white-blue fluorescing oil inclusions in a single quartz crystal from the Barrandian Basin (Czech Republic). The cyclic ion species detected primarily in the yellow fluorescing oil inclusions likely originate from steranes, hopanes, and other tricyclic and tetracyclic terpanes, whereas these are less abundant in the white-blue fluorescing oil inclusions. Depth profiles of the fluid inclusions indicate that the white-blue fluorescing oil inclusions are emptied faster in the ToF-SIMS instrument, presumably due to a higher content of more volatile components than in the yellow fluorescing oil inclusions. The phenanthrene to dibenzothiophene ratio derived from ToF-SIMS of the four inclusion oils from the Barrandian Basin indicates marine clastic sediments as the source rocks for all the inclusion oils. The phenanthrene to alkylphenanthrene ratio derived from ToF-SIMS indicates no major difference in thermal maturity of the oil in the white-blue and yellow fluorescing oil inclusions. Instead, variation in the chemical content of the trapped oil induced by trapping fractionation may be the key control.

Piezoelectricity in nominally centrosymmetric phases

Compound phases often display properties that are symmetry forbidden relative to their nominal, average crystallographic symmetry, even if extrinsic reasons (defects, strain, or imperfections) are not apparent. Specifically, breaking the macroscopic inversion symmetry of a centrosymmetric phase can dominate or significantly change its observed properties while the detailed mechanisms and magnitudes of the deviations of symmetry breaking are often obscure. Here, we choose piezoelectricity as a tool to investigate macroscopic inversion-symmetry breaking in nominally centrosymmetric materials as a prominent example and measure resonant piezoelectric spectroscopy (RPS) and Resonant Ultrasound Spectroscopy (RUS) in 15 compounds, 18 samples, and 21 different phases, including unpoled ferroelectrics, paraelectrics, relaxors, ferroelastics, incipient ferroelectrics, and isotropic materials with low defect concentrations, i.e., NaCl, fused silica, and ${\mathrm{CaF}}_{2}$. We exclude the flexoelectric effect as a source of the observed piezoelectricity yet observe piezoelectricity in all nominally cubic phases of these samples. By scaling the RPS intensities with those of RUS, we calibrate the effective piezoelectric coefficients using single-crystal quartz as standard. Using this scaling we determine the effective piezoelectric modulus in nominally nonpiezoelectric phases, finding that the ``symmetry-forbidden'' piezoelectric effect ranges from $\ensuremath{\sim}1$ to ${10}^{\ensuremath{-}5}$ pm/V ($\ensuremath{\sim}0.5%$ to $\ensuremath{\sim}2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}%$ of the piezoelectric coefficient of poled ferroelectric lead zirconate titanate). The values for the unpoled ferroelectric phase are only slightly higher than those in the paraelectric phase. The extremely low coefficients are well below the detection limit of conventional piezoelectric measurements and demonstrate RPS as a convenient and ultrahighly sensitive method to measure piezoelectricity. We suggest that symmetry-breaking piezoelectricity in nominally centrosymmetric materials and disordered, unpoled ferroelectrics is a common phenomenon.

Determination of Absolute Structure of Chiral Crystals Using Three-Wave X-ray Diffraction

We propose a new method to determine the absolute structure of chiral crystals, which is based on the chiral asymmetry of multiple scattering diffraction. It manifests as a difference in the azimuthal dependence of the forbidden Bragg reflection intensity measured with left and right circularly polarized X-ray beams. Contrary to the existing ones, the suggested method does not use X-ray anomalous dispersion. The difference between the Renninger scans with circularly polarized X-rays has been experimentally demonstrated for the 001 reflection intensities in the right- and left-handed quartz single crystals. A Jmulti-based code on model-independent three-wave-diffraction approach has been developed for quantitative description of our experimental results. The proposed method can be applied to various structures including opaque, organic and monoatomic crystals, even with only light elements. To determine the type of isomer, the Renninger plot of a single forbidden reflection is sufficient.