On-site in situ high-pressure ultrafast pump–probe spectroscopy instrument

2021 ◽  
Vol 92 (11) ◽  
pp. 113002
Author(s):  
Y. L. Wu ◽  
X. Yin ◽  
J. Z. L. Hasaien ◽  
Z. Y. Tian ◽  
Yang Ding ◽  
...  
2015 ◽  
Vol 6 (1) ◽  
Author(s):  
A. E. Gleason ◽  
C. A. Bolme ◽  
H. J. Lee ◽  
B. Nagler ◽  
E. Galtier ◽  
...  

Abstract Pressure- and temperature-induced phase transitions have been studied for more than a century but very little is known about the non-equilibrium processes by which the atoms rearrange. Shock compression generates a nearly instantaneous propagating high-pressure/temperature condition while in situ X-ray diffraction (XRD) probes the time-dependent atomic arrangement. Here we present in situ pump–probe XRD measurements on shock-compressed fused silica, revealing an amorphous to crystalline high-pressure stishovite phase transition. Using the size broadening of the diffraction peaks, the growth of nanocrystalline stishovite grains is resolved on the nanosecond timescale just after shock compression. At applied pressures above 18 GPa the nuclueation of stishovite appears to be kinetically limited to 1.4±0.4 ns. The functional form of this grain growth suggests homogeneous nucleation and attachment as the growth mechanism. These are the first observations of crystalline grain growth in the shock front between low- and high-pressure states via XRD.


2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Shih-Chen Chen ◽  
Kaung-Hsiung Wu ◽  
Jia-Xing Li ◽  
Atsushi Yabushita ◽  
Shih-Han Tang ◽  
...  

1997 ◽  
Vol 141 (3-4) ◽  
pp. 180-184 ◽  
Author(s):  
Achim Reuther ◽  
Alfred Laubereau ◽  
David N Nikogosyan

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.


2021 ◽  
Vol 1 (7) ◽  
pp. 305-305
Author(s):  
Jana Weiß ◽  
Christine Rautenberg ◽  
Thomas Rall ◽  
Christoph Kubis ◽  
Evgenii Kondratenko ◽  
...  

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 312
Author(s):  
Yusuf Tutel ◽  
Gökhan Sevinç ◽  
Betül Küçüköz ◽  
Elif Akhuseyin Yildiz ◽  
Ahmet Karatay ◽  
...  

Meso-substituted borondipyrromethene (BODIPY)-porphyrin compounds that include free base porphyrin with two different numbers of BODIPY groups (BDP-TTP and 3BDP-TTP) were designed and synthesized to analyze intramolecular energy transfer mechanisms of meso-substituted BODIPY-porphyrin dyads and the effect of the different numbers of BODIPY groups connected to free-base porphyrin on the energy transfer mechanism. Absorption spectra of BODIPY-porphyrin conjugates showed wide absorption features in the visible region, and that is highly valuable to increase light-harvesting efficiency. Fluorescence spectra of the studied compounds proved that BODIPY emission intensity decreased upon the photoexcitation of the BODIPY core, due to the energy transfer from BODIPY unit to porphyrin. In addition, ultrafast pump-probe spectroscopy measurements indicated that the energy transfer of the 3BDP-TTP compound (about 3 ps) is faster than the BDP-TTP compound (about 22 ps). Since the BODIPY core directly binds to the porphyrin unit, rapid energy transfer was seen for both compounds. Thus, the energy transfer rate increased with an increasing number of BODIPY moiety connected to free-base porphyrin.


2021 ◽  
Vol 1 (7) ◽  
pp. 308-314
Author(s):  
Jana Weiß ◽  
Christine Rautenberg ◽  
Thomas Rall ◽  
Christoph Kubis ◽  
Evgenii Kondratenko ◽  
...  

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