title: Femtosecond time-resolved X-ray absorption spectroscopy of liquid using a hard X-ray free electron laser in a dual-beam dispersive detection method.
abstract: We present femtosecond time-resolved X-ray absorption spectroscopy of aqueous solution using a hard x-ray free electron laser (SACLA) and a synchronized Ti:sapphire laser. The instrumental response time is 200 fs, and the repetition rate of measurement is 10 Hz. A cylindrical liquid beam 100 μm in diameter of aqueous ammonium iron(III) oxalate solution is photoexcited at 400 nm, and the transient X-ray absorption spectra are measured in the K-edge region of iron, 7.10 - 7.26 keV, using a dual X-ray beam dispersive detection method. Each of the dual beams has the pulse energy of 1.4 μJ, and pump-induced absorbance change on the order of 10(-3) is successfully detected. The photoexcited iron complex exhibits a red shifted iron K-edge with the appearance time constant of 260 fs. The X-ray absorption difference spectra, with and without the pump pulses, are independent of time delay after 1.5 ps up to 100 ps, indicating that the photoexcited species is long-lived.
authors: Yuki
authors: Y
authors: Obara
authors: Tetsuo
authors: T
authors: Katayama
authors: Yoshihiro
authors: Y
authors: Ogi
authors: Takayuki
authors: T
authors: Suzuki
authors: Naoya
authors: N
authors: Kurahashi
authors: Shutaro
authors: S
authors: Karashima
authors: Yuhei
authors: Y
authors: Chiba
authors: Yusuke
authors: Y
authors: Isokawa
authors: Tadashi
authors: T
authors: Togashi
authors: Yuichi
authors: Y
authors: Inubushi
authors: Makina
authors: M
authors: Yabashi
authors: Toshinori
authors: T
authors: Suzuki
authors: Kazuhiko
authors: K
authors: Misawa
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D011829:Radiation Dosage; D012996:Solutions / Q000032:analysis* / Q000737:chemistry* / Q000528:radiation effects; D013052:Spectrometry, X-Ray Emission / Q000295:instrumentation* / Q000379:methods*
chemical_list: D012996:Solutions