51
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Ciarella S, Gang O, Sciortino F. Toward the observation of a liquid-liquid phase transition in patchy origami tetrahedra: a numerical study. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2016; 39:131. [PMID: 28012144 DOI: 10.1140/epje/i2016-16131-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 11/29/2016] [Indexed: 06/06/2023]
Abstract
We evaluate the phase diagram of a model of tetrameric particles where the arms of the tetrahedra are made by six hard cylinders. An interacting site is present on each one of the four vertices allowing the particles to form a bonded network. These model particles provide a coarse-grained but realistic representation of recently synthesised DNA origami tetrahedra. We show that the resulting network is sufficiently empty to allow for partial interpenetration and it is sufficiently flexible to avoid crystallisation (at least on the numerical time scale), satisfying both criteria requested for the observation of a liquid-liquid critical point in tetrahedrally coordinated particles. Grand-canonical simulations provide evidence that, in silico, the model is indeed characterised, in addition to the gas-liquid transition, by a transition between two distinct liquid phases. Our results suggest that an experimental observation of a liquid-liquid transition in a colloidal system can be achieved in the near future.
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Affiliation(s)
- Simone Ciarella
- Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 2, 00185, Roma, Italy.
| | - Oleg Gang
- Chemical Engineering Department, Columbia University, 817 Mudd, New York, USA
| | - Francesco Sciortino
- Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 2, 00185, Roma, Italy
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52
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Mincigrucci R, Matruglio A, Calvi A, Foglia L, Principi E, Simoncig A, Bencivenga F, Dallorto S, Gessini A, Kurdi G, Olynick D, Dhuey S, Sergo R, Lazzarino M, Masciovecchio C, Zilio SD. Toward an integrated device for spatiotemporal superposition of free-electron lasers and laser pulses. OPTICS LETTERS 2016; 41:5090-5093. [PMID: 27805693 DOI: 10.1364/ol.41.005090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Free-electron lasers (FELs) currently represent a step forward on time-resolved investigations on any phase of matter through pump-probe methods involving FELs and laser beams. That class of experiments requires an accurate spatial and temporal superposition of pump and probe beams on the sample, which at present is still a critical procedure. More efficient approaches are demanded to quickly achieve the superposition and synchronization of the beams. Here, we present what we believe is a novel technique based on an integrated device allowing the simultaneous characterization and the fast spatial and temporal overlapping of the beams, reducing the alignment procedure from hours to minutes.
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53
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García G. Synchrotron radiation: basics, methods and applications. CRYSTALLOGR REV 2016. [DOI: 10.1080/0889311x.2016.1203913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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54
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Kunnus K, Josefsson I, Rajkovic I, Schreck S, Quevedo W, Beye M, Weniger C, Grübel S, Scholz M, Nordlund D, Zhang W, Hartsock RW, Gaffney KJ, Schlotter WF, Turner JJ, Kennedy B, Hennies F, de Groot FMF, Techert S, Odelius M, Wernet P, Föhlisch A. Identification of the dominant photochemical pathways and mechanistic insights to the ultrafast ligand exchange of Fe(CO)5 to Fe(CO)4EtOH. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2016; 3:043204. [PMID: 26958587 PMCID: PMC4752567 DOI: 10.1063/1.4941602] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 01/22/2016] [Indexed: 05/19/2023]
Abstract
We utilized femtosecond time-resolved resonant inelastic X-ray scattering and ab initio theory to study the transient electronic structure and the photoinduced molecular dynamics of a model metal carbonyl photocatalyst Fe(CO)5 in ethanol solution. We propose mechanistic explanation for the parallel ultrafast intra-molecular spin crossover and ligation of the Fe(CO)4 which are observed following a charge transfer photoexcitation of Fe(CO)5 as reported in our previous study [Wernet et al., Nature 520, 78 (2015)]. We find that branching of the reaction pathway likely happens in the (1)A1 state of Fe(CO)4. A sub-picosecond time constant of the spin crossover from (1)B2 to (3)B2 is rationalized by the proposed (1)B2 → (1)A1 → (3)B2 mechanism. Ultrafast ligation of the (1)B2 Fe(CO)4 state is significantly faster than the spin-forbidden and diffusion limited ligation process occurring from the (3)B2 Fe(CO)4 ground state that has been observed in the previous studies. We propose that the ultrafast ligation occurs via (1)B2 → (1)A1 → (1)A' Fe(CO)4EtOH pathway and the time scale of the (1)A1 Fe(CO)4 state ligation is governed by the solute-solvent collision frequency. Our study emphasizes the importance of understanding the interaction of molecular excited states with the surrounding environment to explain the relaxation pathways of photoexcited metal carbonyls in solution.
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Affiliation(s)
| | - I Josefsson
- Department of Physics, Stockholm University , AlbaNova University Centre, 10691 Stockholm, Sweden
| | - I Rajkovic
- Max Planck Institute for Biophysical Chemistry , Am Fassberg 11, 37070 Göttingen, Germany
| | | | - W Quevedo
- Institute for Methods and Instrumentation for Synchrotron Radiation Research , Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - M Beye
- Institute for Methods and Instrumentation for Synchrotron Radiation Research , Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - C Weniger
- Institute for Methods and Instrumentation for Synchrotron Radiation Research , Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - S Grübel
- Max Planck Institute for Biophysical Chemistry , Am Fassberg 11, 37070 Göttingen, Germany
| | - M Scholz
- Max Planck Institute for Biophysical Chemistry , Am Fassberg 11, 37070 Göttingen, Germany
| | - D Nordlund
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , Menlo Park, California 94025, USA
| | - W Zhang
- PULSE Institute , SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - R W Hartsock
- PULSE Institute , SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - K J Gaffney
- PULSE Institute , SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - W F Schlotter
- Linac Coherent Light Source, SLAC National Accelerator Laboratory , Menlo Park, California 94025, USA
| | - J J Turner
- Linac Coherent Light Source, SLAC National Accelerator Laboratory , Menlo Park, California 94025, USA
| | - B Kennedy
- Institute for Methods and Instrumentation for Synchrotron Radiation Research , Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - F Hennies
- MAX-lab , P.O. Box 118, 221 00 Lund, Sweden
| | - F M F de Groot
- Department of Chemistry, Utrecht University , Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | | | - M Odelius
- Department of Physics, Stockholm University , AlbaNova University Centre, 10691 Stockholm, Sweden
| | - Ph Wernet
- Institute for Methods and Instrumentation for Synchrotron Radiation Research , Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
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55
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Principi E, Giangrisostomi E, Cucini R, Bencivenga F, Battistoni A, Gessini A, Mincigrucci R, Saito M, Di Fonzo S, D'Amico F, Di Cicco A, Gunnella R, Filipponi A, Giglia A, Nannarone S, Masciovecchio C. Free electron laser-driven ultrafast rearrangement of the electronic structure in Ti. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2016; 3:023604. [PMID: 26798835 PMCID: PMC4720112 DOI: 10.1063/1.4935687] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/02/2015] [Indexed: 05/19/2023]
Abstract
High-energy density extreme ultraviolet radiation delivered by the FERMI seeded free-electron laser has been used to create an exotic nonequilibrium state of matter in a titanium sample characterized by a highly excited electron subsystem at temperatures in excess of 10 eV and a cold solid-density ion lattice. The obtained transient state has been investigated through ultrafast absorption spectroscopy across the Ti M2,3-edge revealing a drastic rearrangement of the sample electronic structure around the Fermi level occurring on a time scale of about 100 fs.
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Affiliation(s)
- E Principi
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - E Giangrisostomi
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - R Cucini
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - F Bencivenga
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - A Battistoni
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - A Gessini
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - R Mincigrucci
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - M Saito
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - S Di Fonzo
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - F D'Amico
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
| | - A Di Cicco
- CNISM, Dip. di Fisica, Università di Camerino , Via Mad. delle Carceri, 62032 Camerino (MC), Italy
| | - R Gunnella
- CNISM, Dip. di Fisica, Università di Camerino , Via Mad. delle Carceri, 62032 Camerino (MC), Italy
| | - A Filipponi
- Dip. di Scienze Fisiche e Chimiche, Università dell'Aquila , Via Vetoio, 67100 L'Aquila, Italy
| | - A Giglia
- IOM-CNR , S.S. 14, km. 163.5, 34149 Basovizza (TS), Italy
| | | | - C Masciovecchio
- Elettra-Sincrotrone Trieste S.C.p.A. , S.S. 14 km 163.5, 34149 Basovizza (TS), Italy
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56
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Wu W, Zhang L, Liu S, Ren H, Zhou X, Li H. Liquid–Liquid Phase Transition in Nanoconfined Silicon Carbide. J Am Chem Soc 2016; 138:2815-22. [DOI: 10.1021/jacs.5b13467] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Weikang Wu
- Key
Laboratory for Liquid−Solid Structural Evolution and Processing
of Materials, Ministry of Education, Shandong University, Jinan 250061, People’s Republic of China
| | - Leining Zhang
- Key
Laboratory for Liquid−Solid Structural Evolution and Processing
of Materials, Ministry of Education, Shandong University, Jinan 250061, People’s Republic of China
| | - Sida Liu
- Key
Laboratory for Liquid−Solid Structural Evolution and Processing
of Materials, Ministry of Education, Shandong University, Jinan 250061, People’s Republic of China
| | - Hongru Ren
- Key
Laboratory for Liquid−Solid Structural Evolution and Processing
of Materials, Ministry of Education, Shandong University, Jinan 250061, People’s Republic of China
| | - Xuyan Zhou
- Key
Laboratory for Liquid−Solid Structural Evolution and Processing
of Materials, Ministry of Education, Shandong University, Jinan 250061, People’s Republic of China
| | - Hui Li
- Key
Laboratory for Liquid−Solid Structural Evolution and Processing
of Materials, Ministry of Education, Shandong University, Jinan 250061, People’s Republic of China
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57
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Shen B, Wang ZY, Dong F, Guo YR, Zhang RJ, Zheng YX, Wang SY, Wang CZ, Ho KM, Chen LY. Dynamics and Diffusion Mechanism of Low-Density Liquid Silicon. J Phys Chem B 2015; 119:14945-51. [PMID: 26540341 DOI: 10.1021/acs.jpcb.5b09138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A first-order phase transition from a high-density liquid to a low-density liquid has been proposed to explain the various thermodynamic anomies of water. It also has been proposed that such liquid-liquid phase transition would exist in supercooled silicon. Computer simulation studies show that, across the transition, the diffusivity drops roughly 2 orders of magnitude, and the structures exhibit considerable tetrahedral ordering. The resulting phase is a highly viscous, low-density liquid silicon. Investigations on the atomic diffusion of such a novel form of liquid silicon are of high interest. Here we report such diffusion results from molecular dynamics simulations using the classical Stillinger-Weber (SW) potential of silicon. We show that the atomic diffusion of the low-density liquid is highly correlated with local tetrahedral geometries. We also show that atoms diffuse through hopping processes within short ranges, which gradually accumulate to an overall random motion for long ranges as in normal liquids. There is a close relationship between dynamical heterogeneity and hopping process. We point out that the above diffusion mechanism is closely related to the strong directional bonding nature of the distorted tetrahedral network. Our work offers new insights into the complex behavior of the highly viscous low density liquid silicon, suggesting similar diffusion behaviors in other tetrahedral coordinated liquids that exhibit liquid-liquid phase transition such as carbon and germanium.
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Affiliation(s)
- B Shen
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China.,Ames Laboratory, U.S. Department of Energy and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - Z Y Wang
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China
| | - F Dong
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China
| | - Y R Guo
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China
| | - R J Zhang
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China
| | - Y X Zheng
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China
| | - S Y Wang
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China.,Ames Laboratory, U.S. Department of Energy and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States.,Key Laboratory for Information Science of Electromagnetic Waves (MoE) , Shanghai, 200433, China
| | - C Z Wang
- Ames Laboratory, U.S. Department of Energy and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - K M Ho
- Ames Laboratory, U.S. Department of Energy and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - L Y Chen
- Key Laboratory of Micro and Nano Photonic Structures (MoE) and Department of Optical Science and Engineering, Fudan University , Shanghai, 200433, China
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58
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Signature of a polyamorphic transition in the THz spectrum of vitreous GeO2. Sci Rep 2015; 5:14996. [PMID: 26459927 PMCID: PMC4602314 DOI: 10.1038/srep14996] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 09/15/2015] [Indexed: 11/09/2022] Open
Abstract
The THz spectrum of density fluctuations, S(Q, ω), of vitreous GeO2 at ambient temperature was measured by inelastic x-ray scattering from ambient pressure up to pressures well beyond that of the known α-quartz to rutile polyamorphic (PA) transition. We observe significant differences in the spectral shape measured below and above the PA transition, in particular, in the 30-80 meV range. Guided by first-principle lattice dynamics calculations, we interpret the changes in the phonon dispersion as the evolution from a quartz-like to a rutile-like coordination. Notably, such a crossover is accompanied by a cusp-like behavior in the pressure dependence of the elastic response of the system. Overall, the presented results highlight the complex fingerprint of PA phenomena on the high-frequency phonon dispersion.
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59
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Zier T, Zijlstra ES, Kalitsov A, Theodonis I, Garcia ME. Signatures of nonthermal melting. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2015; 2:054101. [PMID: 26798822 PMCID: PMC4711650 DOI: 10.1063/1.4928686] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 08/04/2015] [Indexed: 05/22/2023]
Abstract
Intense ultrashort laser pulses can melt crystals in less than a picosecond but, in spite of over thirty years of active research, for many materials it is not known to what extent thermal and nonthermal microscopic processes cause this ultrafast phenomenon. Here, we perform ab-initio molecular-dynamics simulations of silicon on a laser-excited potential-energy surface, exclusively revealing nonthermal signatures of laser-induced melting. From our simulated atomic trajectories, we compute the decay of five structure factors and the time-dependent structure function. We demonstrate how these quantities provide criteria to distinguish predominantly nonthermal from thermal melting.
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Affiliation(s)
- Tobias Zier
- Theoretical Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), Universität Kassel , Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Eeuwe S Zijlstra
- Theoretical Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), Universität Kassel , Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Alan Kalitsov
- MINT, University of Alabama , Tuscaloosa, Alabama 35487, USA
| | - Ioannis Theodonis
- Department of Physics, National Technical University , GR-15773 Zografou, Athens, Greece
| | - Martin E Garcia
- Theoretical Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), Universität Kassel , Heinrich-Plett-Str. 40, 34132 Kassel, Germany
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60
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Zhao G, Yu YJ, Tan XM. Nature of the first-order liquid-liquid phase transition in supercooled silicon. J Chem Phys 2015; 143:054508. [DOI: 10.1063/1.4928194] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- G. Zhao
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, People’s Republic of China
| | - Y. J. Yu
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, People’s Republic of China
| | - X. M. Tan
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, People’s Republic of China
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61
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Spin-liquid polymorphism in a correlated electron system on the threshold of superconductivity. Proc Natl Acad Sci U S A 2015; 112:10316-20. [PMID: 26240327 DOI: 10.1073/pnas.1503559112] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report neutron scattering measurements which reveal spin-liquid polymorphism in an "11" iron chalcogenide superconductor. It occurs when a poorly metallic magnetic state of FeTe is tuned toward superconductivity by substitution of a small amount of tellurium with isoelectronic sulfur. We observe a liquid-like magnetic response, which is described by the coexistence of two disordered magnetic phases with different local structures whose relative abundance depends on temperature. One is the ferromagnetic (FM) plaquette phase observed in undoped, nonsuperconducting FeTe, which preserves the C4 symmetry of the underlying square lattice and is favored at high temperatures, whereas the other is the antiferromagnetic plaquette phase with broken C4 symmetry, which emerges with doping and is predominant at low temperatures. These findings suggest the coexistence of and competition between two distinct liquid states, and a liquid-liquid phase transformation between these states, in the electronic spin system of FeTe(1-x)(S,Se)(x). We have thus discovered the remarkable physics of competing spin-liquid polymorphs in a correlated electron system approaching superconductivity. Our results facilitate an understanding of large swaths of recent experimental data in unconventional superconductors. In particular, the phase with lower C2 local symmetry, whose emergence precedes superconductivity, naturally accounts for a propensity for forming electronic nematic states which have been observed experimentally, in cuprate and iron-based superconductors alike.
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62
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Smallenburg F, Filion L, Sciortino F. Liquid-Liquid Phase Transitions in Tetrahedrally Coordinated Fluids via Wertheim Theory. J Phys Chem B 2015; 119:9076-83. [PMID: 25384011 DOI: 10.1021/jp508788m] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Network interpenetration has been proposed as a mechanism for generating liquid-liquid phase transitions in one component systems. We introduce a model of four coordinated particles, which explicitly treats the system as a mixture of two interacting interpenetrating networks that can freely exchange particles. This model can be solved within Wertheim's theory for associating fluids and shows liquid-liquid phase separations (in addition to the gas-liquid) for a wide range of model parameters. We find that originating a liquid-liquid transition requires a small degree of interpenetrability and a preference for intranetwork bonding. Physically, these requirements can be seen as controlling the softness of the particle-particle interaction and the bond flexibility, in full agreement with recent findings [Smallenburg, F.; Filion, L.; Sciortino, F. Nat. Phys. 2014, 10, 653].
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Affiliation(s)
- Frank Smallenburg
- †Department of Physics, Sapienza, Universitá di Roma, Piazzale Aldo Moro 2, I-00185 Roma, Italy
| | - Laura Filion
- ‡Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, Utrecht 3584 CC, The Netherlands
| | - Francesco Sciortino
- †Department of Physics, Sapienza, Universitá di Roma, Piazzale Aldo Moro 2, I-00185 Roma, Italy
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63
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Singh RS, Bagchi B. Correlation between thermodynamic anomalies and pathways of ice nucleation in supercooled water. J Chem Phys 2015; 140:164503. [PMID: 24784283 DOI: 10.1063/1.4871388] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The well-known classical nucleation theory (CNT) for the free energy barrier towards formation of a nucleus of critical size of the new stable phase within the parent metastable phase fails to take into account the influence of other metastable phases having density/order intermediate between the parent metastable phase and the final stable phase. This lacuna can be more serious than capillary approximation or spherical shape assumption made in CNT. This issue is particularly significant in ice nucleation because liquid water shows rich phase diagram consisting of two (high and low density) liquid phases in supercooled state. The explanations of thermodynamic and dynamic anomalies of supercooled water often invoke the possible influence of a liquid-liquid transition between two metastable liquid phases. To investigate both the role of thermodynamic anomalies and presence of distinct metastable liquid phases in supercooled water on ice nucleation, we employ density functional theoretical approach to find nucleation free energy barrier in different regions of phase diagram. The theory makes a number of striking predictions, such as a dramatic lowering of nucleation barrier due to presence of a metastable intermediate phase and crossover in the dependence of free energy barrier on temperature near liquid-liquid critical point. These predictions can be tested by computer simulations as well as by controlled experiments.
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Affiliation(s)
- Rakesh S Singh
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Biman Bagchi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
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64
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Zhang S, Wang LM, Zhang X, Qi L, Zhang S, Ma M, Liu R. Polymorphism in glassy silicon: inherited from liquid-liquid phase transition in supercooled liquid. Sci Rep 2015; 5:8590. [PMID: 25716054 PMCID: PMC4341220 DOI: 10.1038/srep08590] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 01/28/2015] [Indexed: 01/02/2023] Open
Abstract
Combining molecular dynamics (MD) simulation and Voronoi polyhedral analyses, we discussed the microstructure evolution in liquid and glassy silicon during cooling by focusing on the fraction of various clusters. Liquid-liquid phase transition (LLPT) is detected in supercooled liquid silicon However, freezing the high-density liquid (HDL) to the glassy state is not achieved as the quenching rate goes up to 10(14) K/s. The polyamorphism in glassy silicon is found to be mainly associated with low-density liquid (LDL).
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Affiliation(s)
- Shiliang Zhang
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
- School of Science, Yanshan University, Qinhuangdao 066004, China
| | - Li-Min Wang
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
| | - Xinyu Zhang
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
| | - Li Qi
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
| | - Suhong Zhang
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
- School of Science, Yanshan University, Qinhuangdao 066004, China
| | - Mingzhen Ma
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
| | - Riping Liu
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China
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65
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Abstract
The return of supercooled water to a stable equilibrium condition is an irreversible process which, in large enough samples, takes place adiabatically. We investigated this phenomenon in water by fast imaging techniques. As water freezes, large energy and density fluctuations promote the spatial coexistence of solid and liquid phases at different temperatures. Upon synchronously monitoring the time evolution of the local temperature, we observed a sharp dynamic transition between a fast and a slow decay regime at about 266.6 K. We construe the observed phenomenon in terms of the temperature dependence of heat transfers from solid and liquid volumes already at their bulk coexistence temperature towards adjacent still supercooled liquid regions. These findings can be justified by observing that convective motions induced by thermal gradients in a supercooled liquid near coexistence are rapidly suppressed as the nucleated solid fraction overcomes, at low enough temperatures, a characteristic percolation threshold.
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66
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Poletto L, Frassetto F, Miotti P, Di Cicco A, Finetti P, Grazioli C, Iesari F, Kivimäki A, Stagira S, Coreno M. Spectrometer for X-ray emission experiments at FERMI free-electron-laser. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:103112. [PMID: 25362376 DOI: 10.1063/1.4898315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A portable and compact photon spectrometer to be used for photon in-photon out experiments, in particular x-ray emission spectroscopy, is presented. The instrument operates in the 25-800 eV energy range to cover the full emissions of the FEL1 and FEL2 stages of FERMI. The optical design consists of two interchangeable spherical varied-lined-spaced gratings and a CCD detector. Different input sections can be accommodated, with/without an entrance slit and with/without an additional relay mirror, that allow to mount the spectrometer in different end-stations and at variable distances from the target area both at synchrotron and at free-electron-laser beamlines. The characterization on the Gas Phase beamline at ELETTRA Synchrotron (Italy) is presented.
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Affiliation(s)
- L Poletto
- CNR - Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, I-35131 Padova, Italy
| | - F Frassetto
- CNR - Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, I-35131 Padova, Italy
| | - P Miotti
- CNR - Institute of Photonics and Nanotechnologies (CNR-IFN), via Trasea 7, I-35131 Padova, Italy
| | - A Di Cicco
- Physics Division, School of Science and Technology, Università di Camerino, I-62032 Camerino (MC), Italy
| | - P Finetti
- ELETTRA - Sincrotrone Trieste, Basovizza Area Science Park, S. S. 14 - km 163,5, I-34149, Basovizza (TS), Italy
| | - C Grazioli
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste, Italy
| | - F Iesari
- Physics Division, School of Science and Technology, Università di Camerino, I-62032 Camerino (MC), Italy
| | - A Kivimäki
- CNR-Istituto Officina dei Materiali (CNR-IOM), Laboratorio TASC, I-34149 Trieste, Italy
| | - S Stagira
- Politecnico di Milano - Department of Physics, I-20133 Milano, Italy
| | - M Coreno
- ELETTRA - Sincrotrone Trieste, Basovizza Area Science Park, S. S. 14 - km 163,5, I-34149, Basovizza (TS), Italy
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67
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Zhang K, Li H, Jiang YY. Liquid-liquid phase transition in quasi-two-dimensional supercooled silicon. Phys Chem Chem Phys 2014; 16:18023-8. [PMID: 25050842 DOI: 10.1039/c4cp00694a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Anomalies of the local structural order in quasi-two-dimensional liquid silicon upon cooling are investigated. Results show that the appearance of the left subpeak in pair correlation functions is the signature of the liquid-liquid phase transition (LLPT). The structural origin of the LLPT is the formation of a crystal-like ordered structure with a short-range scale, which in turn forms the local well-organized paracrystalline region. Unlike in the bulk liquid silicon, the stages of the LLPT and liquid-solid phase transition (LSPT) in the quasi-two-dimensional liquid silicon do not overlap. The crystal-like ordered structures formed in the LLPT are precursors which are prepared for the subsequent LSPT. Also observed was a strong interconnection between the local well-organized paracrystalline region and the transition from the typical metal to the semimetal in the two-dimensional silicon. This study will aid in better understanding of the essential phase change in two-dimensional liquid silicon.
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Affiliation(s)
- K Zhang
- National Engineering Research Central for Rare Earth Materials, General Research Institute for Non-Ferrous Metals, GRIREM Advanced Co. Ltd., Beijing 100088, China
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68
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Smallenburg F, Filion L, Sciortino F. Erasing no-man's land by thermodynamically stabilizing the liquid-liquid transition in tetrahedral particles. NATURE PHYSICS 2014; 10:653-657. [PMID: 25264453 PMCID: PMC4173115 DOI: 10.1038/nphys3030] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 06/13/2014] [Indexed: 05/25/2023]
Abstract
One of the most controversial hypotheses for explaining the origin of the thermodynamic anomalies characterizing liquid water postulates the presence of a metastable second-order liquid-liquid critical point [1] located in the "no-man's land" [2]. In this scenario, two liquids with distinct local structure emerge near the critical temperature. Unfortunately, since spontaneous crystallization is rapid in this region, experimental support for this hypothesis relies on significant extrapolations, either from the metastable liquid or from amorphous solid water [3, 4]. Although the liquid-liquid transition is expected to feature in many tetrahedrally coordinated liquids, including silicon [5], carbon [6] and silica, even numerical studies of atomic and molecular models have been unable to conclusively prove the existence of this transition. Here we provide such evidence for a model in which it is possible to continuously tune the softness of the interparticle interaction and the flexibility of the bonds, the key ingredients controlling the existence of the critical point. We show that conditions exist where the full coexistence is thermodynamically stable with respect to crystallization. Our work offers a basis for designing colloidal analogues of water exhibiting liquid-liquid transitions in equilibrium, opening the way for experimental confirmation of the original hypothesis.
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Affiliation(s)
- Frank Smallenburg
- Department of Physics, Sapienza, Universitá di Roma, Piazzale Aldo Moro 2, I-00185, Roma, Italy
| | - Laura Filion
- Soft Condensed Matter and Biophysics, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, Utrecht, 3584 CC, the Netherlands
| | - Francesco Sciortino
- Department of Physics, Sapienza, Universitá di Roma, Piazzale Aldo Moro 2, I-00185, Roma, Italy
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69
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He Y, Li X, Li H, Jiang Y, Bian X. Layering transition in confined silicon. NANOSCALE 2014; 6:4217-4224. [PMID: 24609530 DOI: 10.1039/c3nr06174d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The structure of quasi-2D liquid silicon confined to slit nanopores has been investigated using molecular dynamics (MD) simulations. An obvious structural change from a low-density low-coordinated liquid to a high-density highly coordinated liquid has been found in the confined silicon with the increase of the slit size. This kind of structural transition results from layering in the confined silicon, which disappears with the increase of temperature. In the process of layering transition, the coordination distribution of quasi-2D liquid undergoes an evolutionary process from the initial non-uniform distribution to the final uniform distribution. In addition, our results also indicate that the increase of pressure will also induce a layering transition in the confined silicon.
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Affiliation(s)
- Yezeng He
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, People's Republic of China.
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70
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Wang J, Chakraborty B, Eapen J. Absolute thermodynamic properties of molten salts using the two-phase thermodynamic (2PT) superpositioning method. Phys Chem Chem Phys 2014; 16:3062-9. [PMID: 24398710 DOI: 10.1039/c3cp52632a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We show that the absolute thermodynamic properties of molten salts (mixtures of KCl and LiCl) can be accurately determined from the two-phase thermodynamic (2PT) method that is based on superpositioning of solid-like and gas-like (hard-sphere) vibrational density of states (DoS). The 2PT predictions are in excellent accordance with those from the thermodynamic integration method; the melting point of KCl evaluated from the free energy and the absolute entropy shows close conformity with the experimental/NIST data. The DoS partitioning shows that the Li(+) ions in the eutectic LiCl-KCl molten mixture are largely solid-like, unlike the K(+) and Cl(-) ions, which have a significant gas-like contribution, for temperatures ranging from 773 K to 1300 K. The solid-like states of the Li(+) ions may have practical implications when employed for chemical and nuclear reprocessing applications.
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Affiliation(s)
- Jin Wang
- Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695, USA.
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71
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He Y, Li H, Jiang Y, Li X, Bian X. Liquid-liquid phase transition and structure inheritance in carbon films. Sci Rep 2014; 4:3635. [PMID: 24407276 PMCID: PMC3887372 DOI: 10.1038/srep03635] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 12/13/2013] [Indexed: 11/25/2022] Open
Abstract
Molecular dynamics simulations are performed to study the cooling process of quasi-2D liquid carbon. Our results show an obvious liquid-liquid phase transition (LLPT) from the twofold coordinated liquid to the threefold coordinated liquid with the decrease of temperature, followed by a liquid-solid phase transition (LSPT). The LLPT can be regarded as the preparation stage of LSPT. During the cooling process, the chain structures firstly self-assemble into some ring structures and then aggregate into some stable islands which can further connect together to form a complete polycrystalline film. The threefold coordinated structures play an important role in the formation of atomic rings. The inheritance of the threefold coordinated structures provides essential condition to form rings and islands.
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Affiliation(s)
- Yezeng He
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, People's Republic of China
| | - Hui Li
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, People's Republic of China
| | - Yanyan Jiang
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, People's Republic of China
| | - Xiongying Li
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, People's Republic of China
| | - Xiufang Bian
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, People's Republic of China
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72
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Stimulated X-ray emission for materials science. Nature 2013; 501:191-4. [DOI: 10.1038/nature12449] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 07/09/2013] [Indexed: 11/09/2022]
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73
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74
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Abstract
When a material is heated, generally, it dilates. Here, we find a general trend that the average distance between a center atom and atoms in the first nearest-neighbor shell contracts for several metallic melts upon heating. Using synchrotron X-ray diffraction technique and molecular dynamics simulations, we elucidate that this anomaly is caused by the redistribution of polyhedral clusters affected by temperature. In metallic melts, the high-coordinated polyhedra are inclined to evolve into low-coordinated ones with increasing temperature. As the coordination number decreases, the average atomic distance between a center atom and atoms in the first shell of polyhedral clusters is reduced. This phenomenon is a ubiquitous feature for metallic melts consisting of various-sized polyhedra. This finding sheds light on the understanding of atomic structures and thermal behavior of disordered materials and will trigger more experimental and theoretical studies of liquids, amorphous alloys, glasses, and casting temperature effect on solidification process of crystalline materials.
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75
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Vasisht VV, Sastry S. Liquid-Liquid Phase Transition in Supercooled Silicon. LIQUID POLYMORPHISM 2013. [DOI: 10.1002/9781118540350.ch18] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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76
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77
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Reisman S, Giovambattista N. Glass and liquid phase diagram of a polyamorphic monatomic system. J Chem Phys 2013; 138:064509. [DOI: 10.1063/1.4790404] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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78
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Liu Y, Palmer JC, Panagiotopoulos AZ, Debenedetti PG. Liquid-liquid transition in ST2 water. J Chem Phys 2012; 137:214505. [DOI: 10.1063/1.4769126] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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79
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Kunnus K, Rajkovic I, Schreck S, Quevedo W, Eckert S, Beye M, Suljoti E, Weniger C, Kalus C, Grübel S, Scholz M, Nordlund D, Zhang W, Hartsock RW, Gaffney KJ, Schlotter WF, Turner JJ, Kennedy B, Hennies F, Techert S, Wernet P, Föhlisch A. A setup for resonant inelastic soft x-ray scattering on liquids at free electron laser light sources. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:123109. [PMID: 23277974 DOI: 10.1063/1.4772685] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We present a flexible and compact experimental setup that combines an in vacuum liquid jet with an x-ray emission spectrometer to enable static and femtosecond time-resolved resonant inelastic soft x-ray scattering (RIXS) measurements from liquids at free electron laser (FEL) light sources. We demonstrate the feasibility of this type of experiments with the measurements performed at the Linac Coherent Light Source FEL facility. At the FEL we observed changes in the RIXS spectra at high peak fluences which currently sets a limit to maximum attainable count rate at FELs. The setup presented here opens up new possibilities to study the structure and dynamics in liquids.
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Affiliation(s)
- Kristjan Kunnus
- Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin GmbH, Albert-Einstein-Strasse 15, 12489 Berlin, Germany.
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80
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81
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Cajahuaringa S, de Koning M, Antonelli A. Dynamics near a liquid-liquid phase transition in a non-tetrahedral liquid: The case of gallium. J Chem Phys 2012; 136:064513. [DOI: 10.1063/1.3684550] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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82
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Okada JT, Sit PHL, Watanabe Y, Wang YJ, Barbiellini B, Ishikawa T, Itou M, Sakurai Y, Bansil A, Ishikawa R, Hamaishi M, Masaki T, Paradis PF, Kimura K, Ishikawa T, Nanao S. Persistence of covalent bonding in liquid silicon probed by inelastic x-ray scattering. PHYSICAL REVIEW LETTERS 2012; 108:067402. [PMID: 22401121 DOI: 10.1103/physrevlett.108.067402] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 06/28/2011] [Indexed: 05/31/2023]
Abstract
Metallic liquid silicon at 1787 K is investigated using x-ray Compton scattering. An excellent agreement is found between the measurements and the corresponding Car-Parrinello molecular dynamics simulations. Our results show persistence of covalent bonding in liquid silicon and provide support for the occurrence of theoretically predicted liquid-liquid phase transition in supercooled liquid states. The population of covalent bond pairs in liquid silicon is estimated to be 17% via a maximally localized Wannier function analysis. Compton scattering is shown to be a sensitive probe of bonding effects in the liquid state.
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Affiliation(s)
- J T Okada
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Tsukuba, Ibaraki, Japan
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83
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Abraham JY, Buldyrev SV, Giovambattista N. Liquid and Glass Polymorphism in a Monatomic System with Isotropic, Smooth Pair Interactions. J Phys Chem B 2011; 115:14229-39. [DOI: 10.1021/jp205098a] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joel Y. Abraham
- Department of Physics, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States
| | - Sergey V. Buldyrev
- Department of Physics, Yeshiva University, New York, New York 10033, United States
| | - Nicolas Giovambattista
- Department of Physics, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States
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84
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Xu L, Giovambattista N, Buldyrev SV, Debenedetti PG, Stanley HE. Waterlike glass polyamorphism in a monoatomic isotropic Jagla model. J Chem Phys 2011; 134:064507. [PMID: 21322705 DOI: 10.1063/1.3521486] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We perform discrete-event molecular dynamics simulations of a system of particles interacting with a spherically-symmetric (isotropic) two-scale Jagla pair potential characterized by a hard inner core, a linear repulsion at intermediate separations, and a weak attractive interaction at larger separations. This model system has been extensively studied due to its ability to reproduce many thermodynamic, dynamic, and structural anomalies of liquid water. The model is also interesting because: (i) it is very simple, being composed of isotropically interacting particles, (ii) it exhibits polyamorphism in the liquid phase, and (iii) its slow crystallization kinetics facilitate the study of glassy states. There is interest in the degree to which the known polyamorphism in glassy water may have parallels in liquid water. Motivated by parallels between the properties of the Jagla potential and those of water in the liquid state, we study the metastable phase diagram in the glass state. Specifically, we perform the computational analog of the protocols followed in the experimental studies of glassy water. We find that the Jagla potential calculations reproduce three key experimental features of glassy water: (i) the crystal-to-high-density amorphous solid (HDA) transformation upon isothermal compression, (ii) the low-density amorphous solid (LDA)-to-HDA transformation upon isothermal compression, and (iii) the HDA-to-very-high-density amorphous solid (VHDA) transformation upon isobaric annealing at high pressure. In addition, the HDA-to-LDA transformation upon isobaric heating, observed in water experiments, can only be reproduced in the Jagla model if a free surface is introduced in the simulation box. The HDA configurations obtained in cases (i) and (ii) are structurally indistinguishable, suggesting that both processes result in the same glass. With the present parametrization, the evolution of density with pressure or temperature is remarkably similar to the corresponding experimental measurements on water. Our simulations also suggest that the Jagla potential may reproduce features of the HDA-VHDA transformations observed in glassy water upon compression and decompression. Snapshots of the system during the HDA-VHDA and HDA-LDA transformations reveal a clear segregation between LDA and HDA but not between HDA and VHDA, consistent with the possibility that LDA and HDA are separated by a first order transformation as found experimentally, whereas HDA and VHDA are not. Our results demonstrate that a system of particles with simple isotropic pair interactions, a Jagla potential with two characteristic length scales, can present polyamorphism in the glass state as well as reproducing many of the distinguishing properties of liquid water. While most isotropic pair potential models crystallize readily on simulation time scales at the low temperatures investigated here, the Jagla potential is an exception, and is therefore a promising model system for the study of glass phenomenology.
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Affiliation(s)
- Limei Xu
- WPI-AIMR, Tohoku University, Sendai, Miyagi 980-8577, Japan.
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85
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Desgranges C, Delhommelle J. Role of Liquid Polymorphism during the Crystallization of Silicon. J Am Chem Soc 2011; 133:2872-4. [DOI: 10.1021/ja1117478] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Caroline Desgranges
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58201, United States
| | - Jerome Delhommelle
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58201, United States
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86
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Wernet P. Electronic structure in real time: mapping valence electron rearrangements during chemical reactions. Phys Chem Chem Phys 2011; 13:16941-54. [DOI: 10.1039/c0cp02934c] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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87
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