Dynamical structure analysis of liquid SeBr using by neutron quasi-elastic scattering

Shimakura, Hironori; Kawakita, Yukinobu  ; Inamura, Yasuhiro; Kikuchi, Tatsuya  ; Ueno, Hiroki; Nakamura, Mitsutaka   ; Nakajima, Kenji  ; Kawamura, Seiko   ; Shibata, Kaoru  ; Arai, Masatoshi; Takeda, Shinichi*

Chalcogen-halogen systems have low melting point when chalcogen and halogen proportion is 1:1. At this ratio, selenium bromide consists of chain molecule with Br-Se-Se-Br form, where the bond angle and the dihedral angle are about 104 and 83 respectively. Selenium bromide has strong inter-molecular correlation where each molecule doesn't have enough space to rotate freely due to molecular shape and high density. Quasi-elastic neutron scattering (QENS) of liquid SeBr was performed at AMATERAS which installed in MLF/J-PARC. Measured temperatures were 298 K, 373 K and 473 K. It is interesting that S(Q,E) has two components, one is narrow and the other is broad, at specific Q value which represents inter-molecular correlation. We discussed these two components and the other analysis result of QENS spectrum.