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3. Decoupling lattice and magnetic instabilities in frustrated CuMnO$_2$

Author

Lawler, Keith V., Smith, Dean, Evans, Shaun R., Santos, Antonio M. dos, Molaison, Jamie J., Bos, Jan-Willem G., Mutka, Hannu, Henry, Paul F., Argyriou, Dimitri N., Salamat, Ashkan, and Kimber, Simon A. J.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

The $A$MnO$_{2}$ delafossites ($A$=Na, Cu), are model frustrated antiferromagnets, with triangular layers of Mn$^{3+}$~spins. At low temperatures ($T_{N}$=65 K), a $C2/m \rightarrow P\overline{1}$ transition is found in CuMnO$_2$, which breaks frustration and establishes magnetic order. In contrast to this clean transition, $A$=Na only shows short-range distortions at $T_N$. Here we report a systematic crystallographic, spectroscopic, and theoretical investigation of CuMnO$_2$. We show that, even in stoichiometric samples, non-zero anisotropic Cu displacements co-exist with magnetic order. Using X-ray/neutron diffraction and Raman scattering, we show that high pressures acts to decouple these degrees of freedom. This manifests as an isostuctural phase transition at $\sim$10 GPa, with a reversible collapse of the $c$-axis. This is shown to be the high pressure analog of the $c$-axis negative thermal expansion seen at ambient pressure. DFT simulations confirm that dynamical instabilities of the Cu$^{+}$ cations and edge-shared MnO$_{6}$ layers are intertwined at ambient pressure. However, high pressure selectively activates the former, before an eventual predicted re-emergence of magnetism at the highest pressures. Our results show that the lattice dynamics and local structure of CuMnO$_2$ are quantitatively different to non-magnetic Cu delafossites, and raise questions about the role of intrinsic inhomogeniety in frustrated antiferromagnets., Comment: Submitted version, A.S.A.P. article in Inorganic Chemistry

Published
2021
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8. Pressure-Induced Dislocations and Their Influence on Ionic Transport in Li+-Conducting Argyrodites

Author

Faka, Vasiliki, primary, Agne, Matthias T., additional, Lange, Martin A., additional, Daisenberger, Dominik, additional, Wankmiller, Björn, additional, Schwarzmüller, Stefan, additional, Huppertz, Hubert, additional, Maus, Oliver, additional, Helm, Bianca, additional, Böger, Thorben, additional, Hartel, Johannes, additional, Gerdes, Josef Maximilian, additional, Molaison, Jamie J., additional, Kieslich, Gregor, additional, Hansen, Michael Ryan, additional, and Zeier, Wolfgang G., additional

Published
2024
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11. Origin of anomalous breakdown of Bloch's rule in the Mott-Hubbard insulator MnTe$_2$

Author

Chatterji, Tapan, Santos, Antonio M. dos, Molaison, Jamie J., Hansen, Thomas C., Klotz, Stefan, Tucker, Mathew, Samanta, Kartik, and Saha-Dasgupta, Tanusri

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

We reinvestigate the pressure dependence of the crystal structure and antiferromagnetic phase transition in MnTe$_2$ by the rigorous and reliable tool of high pressure neutron powder diffraction. First-principles density functional theory calculations are carried out in order to gain microscopic insight. The measured N\'eel temperature of MnTe$_2$ is found to show unusually large pressure dependence of $12$ K GPa$^{-1}$. This gives rise to large violation of Bloch's rule given by $\alpha=\frac{d\log T_N}{d\log V}=-\frac{10}{3} \approx -3.3$, to a $\alpha$ value of -6.0 $\pm$ 0.1 for MnTe$_2$. The ab-initio calculation of the electronic structure and the magnetic exchange interactions in MnTe$_2$, for the measured crystal structures at different pressures, gives the pressure dependence of the Ne\'el temperature, $\alpha$ to be -5.61, in close agreement with experimental finding. The microscopic origin of this behavior turns to be dictated by the distance dependence of the cation-anion hopping interaction strength.

Published
2015
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14. High-pressure single-crystal neutron scattering study of magnetic and Fe vacancy orders in (Tl,Rb)2Fe4Se5 superconductor

Author

Ye, Feng, Bao, Wei, Chi, Songxue, Santos, Antonio M. dos, Molaison, Jamie J., Fang, Minghu, Wang, Hangdong, Wang, Qianhui Mao Jinchen, Liu, Juanjuan, and Sheng, Jieming

Subjects
Condensed Matter - Superconductivity
Abstract

The magnetic and iron vacancy orders in superconducting (Tl,Rb)2Fe4Se5 single-crystals are investigated by using a high-pressure neutron diffraction technique. Similar to the temperature effect, the block antiferromagnetic order gradually decreases upon increasing pressure while the Fe vacancy superstructural order remains intact before its precipitous disappearance at the critical pressure Pc = 8.3 GPa. Combined with previously determined Pc for superconductivity, our phase diagram under pressure reveals the concurrence of the block AFM order, the iron vacancy order and superconductivity for the 245 superconductor. A synthesis of current experimental data in a coherent physical picture is attempted., Comment: 4 pages, 4 figures

Published
2014
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15. Giant atomic displacement induced by built-in strain in metastable Mn$_3$O$_4$

Author

Hirai, Shigeto, Santos, Antonio M. dos, Shapiro, Maxwell C., Molaison, Jamie J., Pradhan, Neelam, Guthrie, Malcolm, Tulk, Christopher A., Fisher, Ian R., and Mao, Wendy L.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

We present x-ray, neutron scattering and heat capacity data that reveal a coupled first-order magnetic and structural phase transition of the metastable mixed-valence post-spinel compound Mn$_3$O$_4$ at 210 K. Powder neutron diffraction measurements reveal a magnetic structure in which Mn$^{3+}$ spins align antiferromagnetically along the edge-sharing \emph{a}-axis, with a magnetic propagation vector k = [1/2, 0, 0]. In contrast, the Mn$^{2+}$ spins, which are geometrically frustrated, do not order until a much lower temperature. Although the Mn$^{2+}$ spins do not directly participate in the magnetic phase transition at 210 K, structural refinements reveal a large atomic shift at this phase transition, corresponding to a physical motion of approximately 0.25 {\AA} even though the crystal symmetry remains unchanged. This "giant" response is due to the coupled effect of built-in strain in the metastable post-spinel structure with the orbital realignment of the Mn$^{3+}$ ion., Comment: Main text plus supplemental material

Published
2012

17. Absence of amorphous forms when ice is compressed at low temperature

Author

Tulk, Chris A., Molaison, Jamie J., Makhluf, Adam R., Manning, Craig E., and Klug, Dennis D.

Subjects
Ice -- Mechanical properties -- Thermal properties, Thermodynamics, Water, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Amorphous water ice comes in at least three distinct structural forms, all lacking long-range crystalline order. High-density amorphous ice (HDA) was first produced by compressing ice I to 11 kilobar at temperatures below 130 kelvin, and the process was described as thermodynamic melting.sup.1, implying that HDA is a glassy state of water. This concept, and the ability to transform HDA reversibly into low-density amorphous ice, inspired the two-liquid water model, which relates the amorphous phases to two liquid waters in the deeply supercooled regime (below 228 kelvin) to explain many of the anomalies of water.sup.2 (such as density and heat capacity anomalies). However, HDA formation has also been ascribed.sup.3 to a mechanical instability causing structural collapse and associated with kinetics too sluggish for recrystallization to occur. This interpretation is supported by simulations.sup.3, analogy with a structurally similar system.sup.4, and the observation of lattice-vibration softening as ice is compressed.sup.5,6. It also agrees with recent observations of ice compression at higher temperatures--in the 'no man's land' regime, between 145 and 200 kelvin, where kinetics are faster--resulting in crystalline phases.sup.7,8. Here we further probe the role of kinetics and show that, if carried out slowly, compression of ice I even at 100 kelvin (a region in which HDA typically forms) gives proton-ordered, but non-interpenetrating, ice IX', then proton-ordered and interpenetrating ice XV', and finally ice VIII'. By contrast, fast compression yields HDA but no ice IX, and direct transformation of ice I to ice XV' is structurally inhibited. These observations suggest that HDA formation is a consequence of a kinetically arrested transformation between low-density ice I and high-density ice XV' and challenge theories that connect amorphous ice to supercooled liquid water. Slow compression of ice at low temperature results in the sequential formation of a series of crystalline phases, challenging theories that connect amorphous ice to supercooled liquid water., Author(s): Chris A. Tulk [sup.1] , Jamie J. Molaison [sup.1] , Adam R. Makhluf [sup.2] , Craig E. Manning [sup.2] , Dennis D. Klug [sup.3] Author Affiliations: (1) Neutron Sciences [...]

Published
2019
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18. Methods for neutron diffraction studies on hydride superconductors and other metal hydrides.

Author

Haberl, Bianca, Donnelly, Mary-Ellen, Molaison, Jamie J., Guthrie, Malcolm, and Boehler, Reinhard

Subjects
NEUTRON diffraction, HYDRIDES, DEUTERIUM, HYDROGEN, SUPERCONDUCTORS, LIGHT elements
Abstract

High-pressure neutron diffraction is an extremely useful technique in the quest for making and understanding novel hydride superconductors. Neutron diffraction can be used to directly determine elemental stoichiometries and atomic positions of many light elements such as hydrogen or deuterium, even in the presence of heavy elements such as rare-earth metals. Here, we report on the current status and ongoing developments on high-pressure neutron diffraction for hydride superconductors and other metal hydrides with a special focus on current advancements at the Spallation Neutrons and Pressure (SNAP) beamline of the Spallation Neutron Source at Oak Ridge National Laboratory. For broader context, an overview of high-pressure neutron diffractometers and pressure cells is included together with insight into critical sample considerations. There, attention is given to the requirements for powdered hydride samples and the need for deuterium rather than hydrogen. Additionally, the advantages of angular access and data representation as possible at SNAP are described. We demonstrate the current capability for high-pressure neutron diffraction on two different samples created via hydrogen gas loading, specifically pure deuterium and nickel-deuteride. The deuterium example highlights the usefulness of adding sample materials that facilitate the formation of a good powder while the nickel-deuteride example demonstrates that atomic deuterium positions and stoichiometry can be directly determined. Both examples highlight the importance of large scattering apertures. These enable investigation of the data resolved by scattering angle that is needed to identify parasitic peaks and background features. Finally, future directions beyond current high-pressure neutron powder diffraction are also discussed. [ABSTRACT FROM AUTHOR]

Published
2021
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19. Neutron scattering study of polyamorphic THF·17(H2O) – toward a generalized picture of amorphous states and structures derived from clathrate hydrates.

Author

Brant Carvalho, Paulo H. B., Ivanov, Mikhail, Andersson, Ove, Loerting, Thomas, Bauer, Marion, Tulk, Chris A., Haberl, Bianca, Daemen, Luke L., Molaison, Jamie J., Amann-Winkel, Katrin, Lyubartsev, Alexander P., Bull, Craig L., Funnell, Nicholas P., and Häussermann, Ulrich

Abstract

From crystalline tetrahydrofuran clathrate hydrate, THF–CH (THF·17H2O, cubic structure II), three distinct polyamorphs can be derived. First, THF–CH undergoes pressure-induced amorphization when pressurized to 1.3 GPa in the temperature range 77–140 K to a form which, in analogy to pure ice, may be called high-density amorphous (HDA). Second, HDA can be converted to a densified form, VHDA, upon heat-cycling at 1.8 GPa to 180 K. Decompression of VHDA to atmospheric pressure below 130 K produces the third form, recovered amorphous (RA). Results from neutron scattering experiments and molecular dynamics simulations provide a generalized picture of the structure of amorphous THF hydrates with respect to crystalline THF–CH and liquid THF·17H2O solution (∼2.5 M). Although fully amorphous, HDA is heterogeneous with two length scales for water–water correlations (less dense local water structure) and guest–water correlations (denser THF hydration structure). The hydration structure of THF is influenced by guest–host hydrogen bonding. THF molecules maintain a quasiregular array, reminiscent of the crystalline state, and their hydration structure (out to 5 Å) constitutes ∼23H2O. The local water structure in HDA is reminiscent of pure HDA-ice featuring 5-coordinated H2O. In VHDA, the hydration structure of HDA is maintained but the local water structure is densified and resembles pure VHDA-ice with 6-coordinated H2O. The hydration structure of THF in RA constitutes ∼18 H2O molecules and the water structure corresponds to a strictly 4-coordinated network, as in the liquid. Both VHDA and RA can be considered as homogeneous. [ABSTRACT FROM AUTHOR]

Published
2023
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21. The Mechanism Behind Sno Metallization Under High Pressure

Author

Pesach, Asaf, primary, Nguyen, Long, additional, Gorelli, Federico A., additional, Bini, Roberto, additional, Hevroni, Refael, additional, Nikolaevsky, Mark, additional, Dos-Santos, Antonio F. M., additional, Tulk, Christopher, additional, Molaison, Jamie J. J., additional, Shuker, Ruben, additional, Melchior, Aviva, additional, Caspi, El’ad N., additional, Salem, Ran, additional, Makov, Guy, additional, and Sterer, Eran, additional

Published
2022
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23. 3D-printed B4C collimation for neutron pressure cells

Author

Haberl, Bianca, primary, Molaison, Jamie J., additional, Frontzek, Matthias, additional, Novak, Eric C., additional, Granroth, Garrett E., additional, Goldsby, Desarae, additional, Anderson, David C., additional, and Elliott, Amy M., additional

Published
2021
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24. Decoupling Lattice and Magnetic Instabilities in Frustrated CuMnO2

Author

Lawler, Keith V., primary, Smith, Dean, additional, Evans, Shaun R., additional, dos Santos, Antonio M., additional, Molaison, Jamie J., additional, Bos, Jan-Willem G., additional, Mutka, Hannu, additional, Henry, Paul F., additional, Argyriou, Dimitri N., additional, Salamat, Ashkan, additional, and Kimber, Simon A. J., additional

Published
2021
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25. Pressure Induced Topological Quantum Phase Transition in Weyl Semimetal Td-MoTe2

Author

Guguchia, Zurab, dos Santos, Antonio M, Von Rohr, Fabian O, Molaison, Jamie J, Banerjee, Soham, Rhodes, Daniel, Yin, Jiaxin, Khasanov, Rustem, Hone, James, Uemura, Yasutomo J, Hasan, M Zahid, Luetkens, Hubertus, Bozin, Emil S, Amato, Alex, University of Zurich, and Guguchia, Zurab

Subjects
10120 Department of Chemistry, 540 Chemistry, General Physics and Astronomy, 10192 Physics Institute, 3100 General Physics and Astronomy
Published
2020

27. Pressure Induced Topological Quantum Phase Transition in Weyl Semimetal Td-MoTe2

Author

Guguchia, Zurab, primary, dos Santos, Antonio M., additional, von Rohr, Fabian O., additional, Molaison, Jamie J., additional, Banerjee, Soham, additional, Rhodes, Daniel, additional, Yin, Jiaxin, additional, Khasanov, Rustem, additional, Hone, James, additional, Uemura, Yasutomo J., additional, Hasan, M. Zahid, additional, Luetkens, Hubertus, additional, Bozin, Emil S., additional, and Amato, Alex, additional

Published
2020
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28. Distance-Selected Topochemical Dehydro-Diels–Alder Reaction of 1,4-Diphenylbutadiyne toward Crystalline Graphitic Nanoribbons

Author

Zhang, Peijie, primary, Tang, Xingyu, additional, Wang, Yida, additional, Wang, Xuan, additional, Gao, Dexiang, additional, Li, Yapei, additional, Zheng, Haiyan, additional, Wang, Yajie, additional, Wang, Xinxin, additional, Fu, Riqiang, additional, Tang, Mingxue, additional, Ikeda, Kazutaka, additional, Miao, Ping, additional, Hattori, Takanori, additional, Sano-Furukawa, Asami, additional, Tulk, Christopher A., additional, Molaison, Jamie J., additional, Dong, Xiao, additional, Li, Kuo, additional, Ju, Jing, additional, and Mao, Ho-kwang, additional

Published
2020
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30. 3D-printed B4C collimation for neutron pressure cells.

Author

Haberl, Bianca, Molaison, Jamie J., Frontzek, Matthias, Novak, Eric C., Granroth, Garrett E., Goldsby, Desarae, Anderson, David C., and Elliott, Amy M.

Subjects
*DIAMOND anvil cell, *NEUTRON scattering, *NEUTRON sources, *SMALL-angle neutron scattering, *EXTREME environments, *COLLIMATORS
Abstract

A design for an incident-beam collimator for the Paris–Edinburgh pressure cell is described here. This design can be fabricated from reaction-bonded B4C but also through fast turnaround, inexpensive 3D-printing. 3D-printing thereby also offers the opportunity of composite collimators whereby the tip closest to the sample can exhibit even better neutronic characteristics. Here, we characterize four such collimators: one from reaction-bonded B4C, one 3D-printed and fully infiltrated with cyanoacrylate, a glue, one with a glue-free tip, and one with a tip made from enriched 10B4C. The collimators are evaluated on the Spallation Neutrons and Pressure Diffractometer of the Spallation Neutron Source and the Wide-Angle Neutron Diffractometer at the High Flux Isotope Reactor, both at Oak Ridge National Laboratory. This work clearly shows that 3D-printed collimators perform well and also that composite collimators improve performance even further. Beyond use in the Paris–Edinburgh cell, these findings also open new avenues for collimator designs as clearly more complex shapes are possible through 3D printing. An example of such is shown here with a collimator made for single-crystal samples measured inside a diamond anvil cell. These developments are expected to be highly advantageous for future experimentation in high pressure and other extreme environments and even for the design and deployment of new neutron scattering instruments. [ABSTRACT FROM AUTHOR]

Published
2021
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31. Pressure induced polymerization of acetylide anions in CaC2 and 107 fold enhancement of electrical conductivity† †Electronic supplementary information (ESI) available: Details of GC-MS analysis. See DOI: 10.1039/c6sc02830f Click here for additional data file

Author

Zheng, Haiyan, Wang, Lijuan, Li, Kuo, Yang, Youyou, Wang, Yajie, Wu, Jiajia, Dong, Xiao, Wang, Chun-Hai, Tulk, Christopher A., Molaison, Jamie J., Ivanov, Ilia N., Feygenson, Mikhail, Yang, Wenge, Guthrie, Malcolm, Zhao, Yusheng, Mao, Ho-Kwang, and Jin, Changqing

Subjects
Chemistry
Abstract

Pressure induced polymerization of CaC2 in the amorphous phase is evidenced for the first time, accompanied by a 107 fold enhancement of the electrical conductivity., Transformation between different types of carbon–carbon bonding in carbides often results in a dramatic change of physical and chemical properties. Under external pressure, unsaturated carbon atoms form new covalent bonds regardless of the electrostatic repulsion. It was predicted that calcium acetylide (also known as calcium carbide, CaC2) polymerizes to form calcium polyacetylide, calcium polyacenide and calcium graphenide under high pressure. In this work, the phase transitions of CaC2 under external pressure were systematically investigated, and the amorphous phase was studied in detail for the first time. Polycarbide anions like C6 6– are identified with gas chromatography-mass spectrometry and several other techniques, which evidences the pressure induced polymerization of the acetylide anions and suggests the existence of the polyacenide fragment. Additionally, the process of polymerization is accompanied with a 107 fold enhancement of the electrical conductivity. The polymerization of acetylide anions demonstrates that high pressure compression is a viable route to synthesize novel metal polycarbides and materials with extended carbon networks, while shedding light on the synthesis of more complicated metal organics.

Published
2016

37. Synthesis and Properties of the Helium Clathrate and Defect Perovskite [He2–x□x][CaNb]F6

Author

Ma, Shangye, Hester, Brett R., Lloyd, Anthony J., dos Santos, Antonio M., Molaison, Jamie J., and Wilkinson, Angus P.

Abstract

The defect double perovskite [He2–x□x][CaNb]F6, with helium on its A-site, can be prepared by the insertion of helium into ReO3-type CaNbF6at high pressure. Upon cooling from 300 to 100 K under 0.4 GPa helium, ∼60% of the A-sites become occupied. Helium uptake was quantified by both neutron powder diffraction and gas insertion and release measurements. After the conversion of gauge pressure to fugacity, the uptake of helium by CaNbF6can be described by a Langmuir isotherm. The enthalpy of absorption for helium in [He2–x□x][CaNb]F6is estimated to be ∼+3(1) kJ mol–1, implying that its formation is entropically favored. Helium is able to diffuse through the material on a time scale of minutes at temperatures down to ∼150 K but is trapped at 100 K and below. The insertion of helium into CaNbF6reduces the magnitude of its negative thermal expansion, increases the bulk modulus, and modifies its phase behavior. On compressing pristine CaNbF6, at 50 and 100 K, a cubic (Fm3̅m) to rhombohedral (R3̅) phase transition was observed at <0.20 GPa. However, a helium-containing sample remained cubic at 0.4 GPa and 50 K. CaNbF6, compressed in helium at room temperature, remained cubic to >3.7 GPa, the limit of our X-ray diffraction measurements, in contrast to prior reports that upon compression in a nonpenetrating medium, a phase transition is detected at ∼0.4 GPa.

Published
2024
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38. Next-generation diamond cell and applications to single-crystal neutron diffraction

Author

Haberl, Bianca, primary, Dissanayake, Sachith, additional, Wu, Yan, additional, Myles, Dean A. A., additional, dos Santos, Antonio M., additional, Loguillo, Mark, additional, Rucker, Gerald M., additional, Armitage, Douglas P., additional, Cochran, Malcolm, additional, Andrews, Katie M., additional, Hoffmann, Christina, additional, Cao, Huibo, additional, Matsuda, Masaaki, additional, Meilleur, Flora, additional, Ye, Feng, additional, Molaison, Jamie J., additional, and Boehler, Reinhard, additional

Published
2018
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39. Mechanochemical Synthesis of Carbon Nanothread Single Crystals

Author

Li, Xiang, primary, Baldini, Maria, additional, Wang, Tao, additional, Chen, Bo, additional, Xu, En-shi, additional, Vermilyea, Brian, additional, Crespi, Vincent H., additional, Hoffmann, Roald, additional, Molaison, Jamie J., additional, Tulk, Christopher A., additional, Guthrie, Malcolm, additional, Sinogeikin, Stanislav, additional, and Badding, John V., additional

Published
2017
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40. Wide-angle diamond cell for neutron scattering

Author

Haberl, Bianca, primary, Dissanayake, Sachith, additional, Ye, Feng, additional, Daemen, Luke L., additional, Cheng, Yongqiang, additional, Li, Chen W., additional, Ramirez-Cuesta, A.-J. (Timmy), additional, Matsuda, Masaaki, additional, Molaison, Jamie J., additional, and Boehler, Reinhard, additional

Published
2017
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41. Thermal Expansion and Response to Pressure of Double-ReO3-Type Fluorides NaMVF6(M = Nb, Ta)

Author

Lloyd, Anthony J., Masterson, Eric B., Baxter, Samuel J., Molaison, Jamie J., dos Santos, António M., and Wilkinson, Angus P.

Abstract

Several II–IV double-ReO3-type (DROT) fluorides are known to exhibit strong negative thermal expansion (NTE) over a wide temperature range while retaining a cubic structure down to 120 K or lower. CaZrF6, CaNbF6, CaTiF6, and MgZrF6, embody these properties. In contrast to the behavior of these II–IV materials, the I–V DROT material, NaSbF6, has been reported to display a phase transition from rhombohedral to cubic above 300 K and positive thermal expansion both above and below the transition. In this work, NaNbF6and NaTaF6are shown to undergo first-order cubic-to-rhombohedral transitions on cooling to ∼130 K. Above this transition, NaNbF6shows modest NTE between 160 and 250 K, whereas NaTaF6exhibits near-zero thermal expansion over the range 210–270 K. These I–V systems are elastically softer than their II–IV counterparts, with a zero pressure bulk modulus, K0, of 14.6(8) GPa and first derivative of the bulk modulus with respect to pressure, K0′, of −18(3) for cubic NaNbF6, and K0= 14.47(3) GPa and K0′= −21.56(7) for cubic NaTaF6. When subject to ∼0.3 GPa at 300 K, both compounds exhibit a phase transition from Fm3̅mto R3̅. The R3̅ phases exhibit negative linear compressibility over a limited pressure range. A further transition with phase coexistence occurs at ∼2.5–3.0 GPa for NaNbF6and ∼4.5 GPa for NaTaF6. Compression of NaNbF6in helium at room temperature and below provides no evidence for helium penetration into the structure to form a perovskite with helium on the A-site, as was previously reported for CaZrF6.

Published
2020
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43. Pressure‐Induced Polymerization of Acetylene: Structure‐Directed Stereoselectivity and a Possible Route to Graphane

Author

Sun, Jiangman, primary, Dong, Xiao, additional, Wang, Yajie, additional, Li, Kuo, additional, Zheng, Haiyan, additional, Wang, Lijuan, additional, Cody, George D., additional, Tulk, Christopher A., additional, Molaison, Jamie J., additional, Lin, Xiaohuan, additional, Meng, Yufei, additional, Jin, Changqing, additional, and Mao, Ho‐kwang, additional

Published
2017
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44. Deuterium Isotope Effects in Polymerization of Benzene under Pressure

Author

Cai, Weizhao, primary, Dunuwille, Mihindra, additional, He, Jiangang, additional, Taylor, Trevor V., additional, Hinton, Jasmine K., additional, MacLean, Mary C., additional, Molaison, Jamie J., additional, dos Santos, Antonio M., additional, Sinogeikin, Stanislav, additional, and Deemyad, Shanti, additional

Published
2017
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45. Pressure induced polymerization of acetylide anions in CaC2 and 107 fold enhancement of electrical conductivity

Author

Zheng, Haiyan, primary, Wang, Lijuan, additional, Li, Kuo, additional, Yang, Youyou, additional, Wang, Yajie, additional, Wu, Jiajia, additional, Dong, Xiao, additional, Wang, Chun-Hai, additional, Tulk, Christopher A., additional, Molaison, Jamie J., additional, Ivanov, Ilia N., additional, Feygenson, Mikhail, additional, Yang, Wenge, additional, Guthrie, Malcolm, additional, Zhao, Yusheng, additional, Mao, Ho-Kwang, additional, and Jin, Changqing, additional

Published
2017
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46. Polymerization of Acetonitrile via a Hydrogen Transfer Reaction from CH 3 to CN under Extreme Conditions

Author

Zheng, Haiyan, primary, Li, Kuo, additional, Cody, George D., additional, Tulk, Christopher A., additional, Dong, Xiao, additional, Gao, Guoying, additional, Molaison, Jamie J., additional, Liu, Zhenxian, additional, Feygenson, Mikhail, additional, Yang, Wenge, additional, Ivanov, Ilia N., additional, Basile, Leonardo, additional, Idrobo, Juan‐Carlos, additional, Guthrie, Malcolm, additional, and Mao, Ho‐kwang, additional

Published
2016
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47. Polymerization of Acetonitrile via a Hydrogen Transfer Reaction from CH3 to CN under Extreme Conditions

Author

Zheng, Haiyan, primary, Li, Kuo, additional, Cody, George D., additional, Tulk, Christopher A., additional, Dong, Xiao, additional, Gao, Guoying, additional, Molaison, Jamie J., additional, Liu, Zhenxian, additional, Feygenson, Mikhail, additional, Yang, Wenge, additional, Ivanov, Ilia N., additional, Basile, Leonardo, additional, Idrobo, Juan‐Carlos, additional, Guthrie, Malcolm, additional, and Mao, Ho‐kwang, additional

Published
2016
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48. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

Author

Makowska, Małgorzata G., primary, Theil Kuhn, Luise, additional, Cleemann, Lars N., additional, Lauridsen, Erik M., additional, Bilheux, Hassina Z., additional, Molaison, Jamie J., additional, Santodonato, Louis J., additional, Tremsin, Anton S., additional, Grosse, Mirco, additional, Morgano, Manuel, additional, Kabra, Saurabh, additional, and Strobl, Markus, additional

Published
2015
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