<i>In-situ</i>combined X-ray diffraction and electrical resistance measurements at high pressures and temperatures in diamond anvil cells

Kuznetsov, Alexei; Dmitriev, Vladimir; Volkova, Yu.V.; Kurnosov, Alexander; Dubrovinsky, Leonid

doi:10.1080/08957950701254197

Cited by 7 publications

(4 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This phenomenon of a sudden resistance increase at high pressure was observed in all our bulk Te samples as well as in our Te NCs. It is generally accepted that a sudden resistance increase is an indication of a phase transition at high pressure [29,30]. Therefore, all our samples undergo two phase transitions at room temperature, near 7.2 and 10.3 GPa (20 nm NCs), 5.9 and 8.8 GPa (90 nm NCs), and 4.0 and 6.8 GPa (bulk Te).…”

Section: Resultsmentioning

confidence: 71%

Spherical hexagonal tellurium nanocrystals: fabrication and size-dependent structural phase transition at high pressure

Deng¹,

Bao²,

Cao³

et al. 2008

Nanotechnology

View full text Add to dashboard Cite

Single-crystalline spherical nearly monodisperse tellurium (Te) nanocrystals (NCs) with average diameters of 20 and 90 nm, respectively, have been fabricated for the first time by a facile solution sonochemistry process. The structural characterizations show that the as-synthesized Te NCs have pure hexagonal structure, as revealed by x-ray diffraction (XRD), selected-area electron diffraction (SAED), energy-dispersive x-ray (EDX) spectroscopy, and high-resolution transmission electron microscopy (HRTEM) methods. The size-dependent structural phase transition of Te NCs up to the high pressure of 20 GPa has been investigated in a diamond anvil cell using resistance measurement at room temperature, and compared with the behavior of bulk Te under identical conditions. The experimental results indicate that 20 nm Te NCs, 90 nm NCs, and bulk Te all undergo two phase transitions up to 20 GPa, their respective transition pressures being about 7.2 and 10.3 GPa, 5.9 and 8.8 GPa, and 4.0 and 6.8 GPa. This indicates that the phase transition pressures are higher for the smaller NCs. In this paper we discuss the size-dependent structural phase transitions, the sluggishness of the phase transition process, and the fluctuating properties of the phase transition products at high pressure. The present work might open an avenue to real-time detection of the dynamics of the phase transition in bulk and nanoscale materials at high pressure, and also could serve as a guide to tailoring the microscopic properties of materials.

show abstract

Section: Resultsmentioning

confidence: 71%

Spherical hexagonal tellurium nanocrystals: fabrication and size-dependent structural phase transition at high pressure

Deng¹,

Bao²,

Cao³

et al. 2008

Nanotechnology

View full text Add to dashboard Cite

show abstract

“…The two rhenium foil halves were coated with a gold layer roughly 2-mm thick using a simple sputter coater and then glued onto a synthetic single-crystal diamond, thus providing a split-gasket hole configuration for the sample chamber. A platinum wire with 20 mm diameter was used in a linear four-point probe scheme (see Kuznetsov et al 36 for technical details). Current was supplied through two platinum leads glued onto different halves of the split gasket, and voltage was measured using the other two leads.…”

Section: Methodsmentioning

confidence: 99%

Effect of iron oxidation state on the electrical conductivity of the Earth’s lower mantle

et al. 2013

Self Cite

View full text Add to dashboard Cite

Iron can adopt different spin states in the lower mantle. Previous studies indicate that the dominant lower-mantle phase, magnesium silicate perovskite (which contains at least half of its iron as Fe 3þ ), undergoes a Fe 3þ high-spin to low-spin transition that has been suggested to cause seismic velocity anomalies and a drop in laboratory-measured electrical conductivity. Here we apply a new synchrotron-based method of Mössbauer spectroscopy and show that Fe 3þ remains in the high-spin state in lower-mantle perovskite at conditions throughout the lower mantle. Electrical conductivity measurements show no conductivity drop in samples with high Fe 3þ , suggesting that the conductivity drop observed previously on samples with high Fe 2þ is due to a transition of Fe 2þ to the intermediate-spin state. Correlation of transport and elastic properties of lower-mantle perovskite with electromagnetic and seismic data may provide a new probe of heterogeneity in the lower mantle.

show abstract

“…Kuznetsov et al (2007) measured resistance of iron with 10 at.% nickel alloy by using quasi-four-terminal methods down to 1.3 GPa. Assuming that the resistivity at 1.3 GPa is equivalent to its literature value at 1 bar (Ho et al, 1983), we calculated the resistivity in Kuznetsov et al (2007)'s experiments at high pressure. These values show excellent agreement with our results (Fig.…”

Section: Difference In Resistivity Between Bcc and Hcp Phasesmentioning

confidence: 99%

“…Blue (15 wt.% Ni), green (10 wt.% Ni), and orange (5 wt.% Ni) circles indicate the present measurements. Previous measurements are indicated by red and pink circles and diamonds (pure iron;Gomi et al, 2013), green squares (10 at.% Ni;Kuznetsov et al, 2007), black squares (pure iron;Jaccard et al, 2002), gray and white triangles (pure iron;Seagle et al, 2013). The first-principles calculations reported bySha and Cohen (2011) andGomi et al (2013) on pure iron are shown by gray broken and black solid lines, respectively.…”

mentioning

confidence: 96%

Electrical resistivity and thermal conductivity of hcp Fe–Ni alloys under high pressure: Implications for thermal convection in the Earth’s core

Gomi

Hirose

2015

Physics of the Earth and Planetary Interiors

View full text Add to dashboard Cite

In-situcombined X-ray diffraction and electrical resistance measurements at high pressures and temperatures in diamond anvil cells

Cited by 7 publications

References 25 publications

Spherical hexagonal tellurium nanocrystals: fabrication and size-dependent structural phase transition at high pressure

Spherical hexagonal tellurium nanocrystals: fabrication and size-dependent structural phase transition at high pressure

Effect of iron oxidation state on the electrical conductivity of the Earth’s lower mantle

Electrical resistivity and thermal conductivity of hcp Fe–Ni alloys under high pressure: Implications for thermal convection in the Earth’s core

Contact Info

Product

Resources

About