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arXiv · 2205.07145

Metastable structure of photoexcited WO$_{3}$ determined by the pump--probe extended X-ray absorption fine structure spectroscopy and constrained thorough search analysis

Daiki Kido·Hiromitsu Uehara·Satoru Takakusagi·Jun-ya Hasegawa·Kiyotaka Asakura·Yohei Uemura·Yuki Wakisaka·Akihiro Koide·Toshihiko Yokoyama·Yasuhiro Niwa·Shunsuke Nozawa·Kohei Ichiyanagi·Ryo Fukaya·Shin-ichi Adachi·Harry Jenkins·Tokushi Sato
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Abstract

We have determined the local structure of photoexcited metastable WO$_3$ created 150 ps after 400 nm laser irradiation by the pulse pump--probe L$_3$-edge extended X-ray absorption fine structure spectroscopy and the constrained thorough search analysis. We have found a highly distorted octahedral local structure with one of the shortest W=O bonds being further shortened to 1.66 \AA while the other five bonds were elongated even though theoretical calculations predicted the reverse change. We discuss this contradiction and propose a possible structure for the metastable state.

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Daiki Kido, Hiromitsu Uehara, Satoru Takakusagi, Jun-ya Hasegawa, Kiyotaka Asakura, Yohei Uemura, Yuki Wakisaka, Akihiro Koide, Toshihiko Yokoyama, Yasuhiro Niwa, Shunsuke Nozawa, Kohei Ichiyanagi, Ryo Fukaya, Shin-ichi Adachi, Harry Jenkins, Tokushi Sato. 2022-05-14. Metastable structure of photoexcited WO$_{3}$ determined by the pump--probe extended X-ray absorption fine structure spectroscopy and constrained thorough search analysis. https://arxiv.org/abs/2205.07145

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