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DOE OSTI · 2565447

Non-thermal structural transformation of diamond driven by x-rays

Heimann, Philip (ORCID:000000022973664X)·Hartley, Nicholas J. (ORCID:0000000262682436)·Inoue, Ichiro·Tkachenko, Victor (ORCID:000000020245145X)·Antoine, Andre (ORCID:0000000308270219)·Dorchies, Fabien (ORCID:0000000259229585)·Falcone, Roger (ORCID:0000000254236022)·Gaudin, Jérôme (ORCID:0000000213110757)·Höppner, Hauke (ORCID:0009000019295097)·Inubushi, Yuichi (ORCID:0000000316083819)·Kapcia, Konrad J. (ORCID:0000000188421886)·Lee, Hae Ja (ORCID:0000000240355637)·Lipp, Vladimir (ORCID:0000000258282296)·Martinez, Paloma (ORCID:0000000326241809)·Medvedev, Nikita (ORCID:0000000304911090)·Tavella, Franz (ORCID:0000000277510979)·Toleikis, Sven (ORCID:0009000821367780)·Yabashi, Makina (ORCID:0000000224721684)·Yabuuchi, Toshinori (ORCID:0000000306387640)·Yamada, Jumpei (ORCID:0000000254764327)·Ziaja, Beata (ORCID:0000000301720731)
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Abstract

Intense x-ray pulses can cause the non-thermal structural transformation of diamond. At the SACLA XFEL facility, pump x-ray pulses triggered this phase transition, and probe x-ray pulses produced diffraction patterns. Time delays were observed from 0 to 250 fs, and the x-ray dose varied from 0.9 to 8.0 eV/atom. The intensity of the (111), (220), and (311) diffraction peaks decreased with time, indicating a disordering of the crystal lattice. From a Debye–Waller analysis, the rms atomic displacements perpendicular to the (111) planes were observed to be significantly larger than those perpendicular to the (220) or (311) planes. At a long time delay of 33 ms, graphite (002) diffraction indicates that graphitization did occur above a threshold dose of 1.2 eV/atom. These experimental results are in qualitative agreement with XTANT+ simulations using a hybrid model based on density-functional tight-binding molecular dynamics.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCarbon based materialsChemistryDensity-functional tight-bindingFree electron lasersMolecular dynamicsPhase transitionsPhysics

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Heimann, Philip (ORCID:000000022973664X), Hartley, Nicholas J. (ORCID:0000000262682436), Inoue, Ichiro, Tkachenko, Victor (ORCID:000000020245145X), Antoine, Andre (ORCID:0000000308270219), Dorchies, Fabien (ORCID:0000000259229585), Falcone, Roger (ORCID:0000000254236022), Gaudin, Jérôme (ORCID:0000000213110757), Höppner, Hauke (ORCID:0009000019295097), Inubushi, Yuichi (ORCID:0000000316083819), Kapcia, Konrad J. (ORCID:0000000188421886), Lee, Hae Ja (ORCID:0000000240355637), Lipp, Vladimir (ORCID:0000000258282296), Martinez, Paloma (ORCID:0000000326241809), Medvedev, Nikita (ORCID:0000000304911090), Tavella, Franz (ORCID:0000000277510979), Toleikis, Sven (ORCID:0009000821367780), Yabashi, Makina (ORCID:0000000224721684), Yabuuchi, Toshinori (ORCID:0000000306387640), Yamada, Jumpei (ORCID:0000000254764327), Ziaja, Beata (ORCID:0000000301720731). 2023-10-27. Non-thermal structural transformation of diamond driven by x-rays. https://doi.org/10.1063/4.0000193

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