Picón, A.A.PicónLehmann, C. S.C. S.LehmannBostedt, C.C.BostedtRudenko, A.A.RudenkoMarinelli, A.A.MarinelliOsipov, T.T.OsipovRolles, D.D.RollesBerrah, N.N.BerrahBomme, C.C.BommeBucher, M.M.BucherDoumy, G.G.DoumyErk, B.B.ErkFerguson, K. R.K. R.FergusonGorkhover, T.T.GorkhoverHo, P. J.P. J.HoKanter, E. P.E. P.KanterKrässig, B.B.KrässigKrzywinski, J.J.KrzywinskiLutman, A. A.A. A.LutmanMarch, A. M.A. M.MarchMoonshiram, D.D.MoonshiramRay, D.D.RayYoung, L.L.YoungPratt, S. T.S. T.PrattSouthworth, S. H.S. H.Southworth2022-12-142022-12-142016-05-23https://resolver.sub.uni-goettingen.de/purl?gro-2/118680New capabilities at X-ray free-electron laser facilities allow the generation of two-colour femtosecond X-ray pulses, opening the possibility of performing ultrafast studies of X-ray-induced phenomena. Particularly, the experimental realization of hetero-site-specific X-ray-pump/X-ray-probe spectroscopy is of special interest, in which an X-ray pump pulse is absorbed at one site within a molecule and an X-ray probe pulse follows the X-ray-induced dynamics at another site within the same molecule. Here we show experimental evidence of a hetero-site pump-probe signal. By using two-colour 10-fs X-ray pulses, we are able to observe the femtosecond time dependence for the formation of F ions during the fragmentation of XeF2 molecules following X-ray absorption at the Xe site.enjournal_article10.1038/ncomms1165227212390