1 Structure and single particle dynamics of the vapour- liquid interface of acetone-CO 2 mixtures Balázs Fábián, 1 George Horvai, 2 Abdenacer Idrissi 3 and Pál Jedlovszky 4* 1 Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, CZ-16610 Prague 6, Czech Republic 2 Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Szt. Gellért tér 4, H-1111 Budapest, Hungary 3 Laboratoire de Spectrochimie Infrarouge et Raman (UMR CNRS 8516), University of Lille Nord de France, 59655 Villeneuve d’Ascq Cedex, France 4 Department of Chemistry, Eszterházy Károly University, Leányka utca 6, H- 3300 Eger, Hungary * Electronic mail: jedlovszky.pal@uni-eszterhazy.hu (PJ)