Transverse excitations in liquid Fe, Cu and Zn. (29th April 2015)

• Record Type: Journal Article
• Authors: Hosokawa, S; Inui, M; Kajihara, Y; Tsutsui, S; Baron, A Q R
• Is Part Of: Journal of physics. Volume 27:Number 19(2015)
• Publication Date: 2015-04-29
• Subjects: liquid metals -- dynamics -- phonons -- transverse; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/0953-8984/27/19/194104
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Transverse acoustic (TA) excitation modes were observed in inelastic x-ray scattering spectra of liquid Fe, Cu and Zn. From the analysis of current correlation functions, we concluded that TA excitation modes can experimentally be detected through the quasi-TA branches in the longitudinal current correlation spectra in these liquid metals. The microscopic elastic constants are estimated and a characteristic difference from macroscopic polycrystalline value was found in Poisson's ratio of liquid Fe, which shows an extremely softer value of ∼0.38 compared with the macroscopic value of ∼0.275. The lifetime of the TA modes were determined to be ∼0.45 ps for liquid Fe and Cu and ∼0.55 ps for liquid Zn, reflecting different interatomic correlations between liquid transition metals and non-transition metals. The propagation length of the TA modes are ∼0.85 nm in all of liquid metals, corresponding to the size of icosahedral or similar size of cages formed instantaneously in these liquid metals.