XAS and RIXS study of acetic acid and methyl formate in liquid

O Takahashi,N Nishida,T Tokushima,Y Horikawa,S Kanai

doi:10.1088/1742-6596/712/1/012040

Abstract

Structure of acetic acid (AA) and methyl formate (MF) in the liquid phase is studied using X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) experimentally and theoretically. Two distinct XES spectra are observed by tuning photon energy for both molecules. Model structure in the liquid phase is constructed using the classical and first principle molecular dynamics simulations, and XES spectra are calculated using density functional theory. Calculated XES spectra are consistent with experimental ones. The effect of core-hole induced excited state molecular dynamics are discussed.

Highlights

Soft X-ray spectroscopy is one of powerful tools to investigate a local structure of various materials in the gas or condensed phases [1, 2]
We investigate methyl formate (MF) in the liquid phase using X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) in comparison with acetic acid (AA) [4]
By tuning photon energy, site-selective XES spectra can be observed for MF

Summary

Introduction

Soft X-ray spectroscopy is one of powerful tools to investigate a local structure of various materials in the gas or condensed phases [1, 2]. To interpret the observed spectra theoretical analysis with the model structure is needed. Tokushima and his coworkers investigated structure of acetic acid (AA) in the liquid phase using resonant X-ray emission spectroscopy (resonant XES) [3], a technique that can be called resonant inelastic X-ray scattering (RIXS). We investigate methyl formate (MF) in the liquid phase using X-ray absorption spectroscopy (XAS) and XES in comparison with AA [4]. To elucidate feature of XES spectra of these liquids theoretical model structure was constructed using the first principle molecular dynamics simulations, and XES spectra were produced within the framework of density functional theory (DFT) using the cluster model. Note that Robin et al [5] reported studies for AA in the gas phase by electron energy loss spectroscopy (EELS)

Experimental measurements

Theoretical methods

Results and Discussion

Conclusion