Search Results - "Crichton, W. A"

Seismic velocities of CaSiO3 perovskite can explain LLSVPs in Earth’s lower mantle by Thomson, A. R., Crichton, W. A., Brodholt, J. P., Wood, I. G., Siersch, N. C., Muir, J. M. R., Dobson, D. P., Hunt, S. A.

“…Seismology records the presence of various heterogeneities throughout the lower mantle 1 , 2 , but the origins of these signals—whether thermal or…”
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Role of disorder in the thermodynamics and atomic dynamics of glasses by Chumakov, A I, Monaco, G, Fontana, A, Bosak, A, Hermann, R P, Bessas, D, Wehinger, B, Crichton, W A, Krisch, M, Rüffer, R, Baldi, G, Carini, Jr, G, Carini, G, D'Angelo, G, Gilioli, E, Tripodo, G, Zanatta, M, Winkler, B, Milman, V, Refson, K, Dove, M T, Dubrovinskaia, N, Dubrovinsky, L, Keding, R, Yue, Y Z

“…We measured the density of vibrational states (DOS) and the specific heat of various glassy and crystalline polymorphs of SiO2. The typical (ambient) glass…”
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Equivalence of the boson peak in glasses to the transverse acoustic van Hove singularity in crystals by Chumakov, A I, Monaco, G, Monaco, A, Crichton, W A, Bosak, A, Rüffer, R, Meyer, A, Kargl, F, Comez, L, Fioretto, D, Giefers, H, Roitsch, S, Wortmann, G, Manghnani, M H, Hushur, A, Williams, Q, Balogh, J, Parliński, K, Jochym, P, Piekarz, P

“…We compare the atomic dynamics of the glass to that of the relevant crystal. In the spectra of inelastic scattering, the boson peak of the glass appears higher…”
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Nature of the first-order phase transition in fluid phosphorus at high temperature and pressure by Monaco, G, Falconi, S, Crichton, W A, Mezouar, M

“…An in situ x-ray diffraction experiment has been performed on phosphorus to characterize the liquid-liquid transition which occurs at high temperature and…”
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Effect of densification on the density of vibrational states of glasses by Monaco, A, Chumakov, A I, Monaco, G, Crichton, W A, Meyer, A, Comez, L, Fioretto, D, Korecki, J, Rüffer, R

“…We studied the effect of densification on the vibrational dynamics of a Na(2)FeSi(3)O(8) glass. The density of vibrational states (DOS) has been measured using…”
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Iron-silica interaction at extreme conditions and the electrically conducting layer at the base of Earth's mantle by Dubrovinsky, L, Dubrovinskaia, N, Langenhorst, F, Dobson, D, Rubie, D, Geßmann, C, Abrikosov, I. A, Johansson, B, Baykov, V. I, Vitos, L, Bihan, T. Le, Crichton, W. A, Dmitriev, V, Weber, H.-P

“…The boundary between the Earth's metallic core and its silicate mantle is characterized by strong lateral heterogeneity and sharp changes in density, seismic…”
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Beating the miscibility barrier between iron group elements and magnesium by high-pressure alloying by DUBROVINSKAIA, N, DUBROVINSKY, L, ABRIKOSOV, I. A, KANTOR, I, CRICHTON, W. A, DMITRIEV, V, PRAKAPENKA, V, SHEN, G, VITAS, L, AHUJA, R, JOHANSSON, B

“…Iron and magnesium are almost immiscible at ambient pressure. The low solubility of Mg in Fe is due to a very large size mismatch between the alloy components…”
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SrWO4 at high pressures by Grzechnik, A., Crichton, W. A., Hanfland, M.

“…Room‐temperature high‐pressure behaviour of SrWO4 scheelite (I41/a, Z = 4) has been studied to 20.7 GPa in a diamond anvil cell using synchrotron…”
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High-temperature equation of state of vanadium by Crichton, W. A., Guignard, J., Bailey, E., Dobson, D. P., Hunt, S. A., Thomson, A. R.

“…The unit cell dimensions of vanadium, NaCl and Au have been collected to 11. 5 GPa and 1000 K by powder X-ray diffraction and are used to constrain a practical…”
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A New Polymorph of ZrW2O8 Synthesized at High Pressures and High Temperatures by Grzechnik, A, Crichton, W. A, Syassen, K, Adler, P, Mezouar, M

“…Pressure-induced amorphization of materials with negative thermal expansion is believed to arise from uncorrelated tiltings of polyhedra, kinetically frozen in…”
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Equilibrium high entropy phases in X-NbTaTiZr (X = Al,V,Cr and Sn) multiprincipal component alloys by Poletti, M.G., Branz, S., Fiore, G., Szost, B.A., Crichton, W.A., Battezzati, L.

“…X-NbTaTiZr, with X=Al,V,Cr and Sn, potential High Entropy Alloys obtained by arc melting were annealed to reveal the equilibrium constitution. AlNbTaTiZr and…”
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CaCO3-III and CaCO3-VI, high-pressure polymorphs of calcite: Possible host structures for carbon in the Earth's mantle by Merlini, M., Hanfland, M., Crichton, W.A.

“…Calcite, CaCO3, undergoes several high pressure phase transitions. We report here the crystal structure determination of the CaCO3-III and CaCO3-VI…”
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Structure of fluid phosphorus at high temperature and pressure: An x-ray diffraction study by FALCONI, S, CRICHTON, W. A, MEZOUAR, M, MONACO, G, NARDONE, M

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Observation of the high-pressure Pmma phase in InAs: A combined X-ray absorption and diffraction study by Pascarelli, S, Aquilanti, G, Crichton, W. A, Bihan, T. Le, Mezouar, M, Panfilis, S. De, Itié, J. P, Polian, A

“…X-ray absorption and diffraction measurements on InAs up to 80 GPa reveal the presence of a high-pressure short-range chemically disordered Pmma structure and…”
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Strength of fayalite up to 8.5 GPa by Guignard, J., Bystricky, M., Béjina, F., Crichton, W. A., Proietti, A., Tercé, N.

“…A dense polycrystalline aggregate of synthetic fayalite (Fe 2 SiO 4 ) was deformed up to 8.5 GPa at room temperature in the D-DIA press installed at the…”
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Equations of state of magnesium silicates anhydrous B and superhydrous B by Crichton, W. A., Ross, N. L., Gasparik, T.

“…High-pressure single crystal X-ray diffraction experiments of phase anhydrous B and superhydrous B have been carried out to 7.3 and 7.7 GPa, respectively, at…”
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Noblest of all metals is structurally unstable at high pressure by Dubrovinsky, L, Dubrovinskaia, N, Crichton, W A, Mikhaylushkin, A S, Simak, S I, Abrikosov, I A, de Almeida, J S, Ahuja, R, Luo, W, Johansson, B

“…In a series of experiments in externally electrically heated diamond anvil cells we demonstrate that at pressures above approximately 240 GPa gold adopts a…”
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Density of vibrational states of a hyperquenched glass by Monaco, A, Chumakov, A I, Yue, Y-Z, Monaco, G, Comez, L, Fioretto, D, Crichton, W A, Rüffer, R

“…The vibrational density of states of a hyperquenched and an annealed glass has been measured using nuclear inelastic scattering. The hyperquenched sample shows…”
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High-pressure X-ray diffraction study of InAs by Aquilanti, G., Crichton, W.A., Le Bihan, T., Pascarelli, S.

“…Structural phase transitions in III–V semiconductors have been the subject of numerous experimental and theoretical studies. Contrary to traditional…”
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Collimator for inelastic x-ray scattering experiments at high temperature and pressure conditions by Falconi, S., Monaco, G., Crichton, W. A., Mezouar, M., Verbeni, R.

“…A two-slits collimator designed for inelastic X-ray scattering (IXS) experiments using the Paris-Edinburgh large volume press is presented here. This…”
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