This repository contains the underlying data for the paper entitled "Observation of site-selective chemical bond changes via ultrafast chemical shifts". The uploaded data are preprocessed data measured at the LCLS SLAC facility. Each individual file contains the measurements at a set delay time and spectrometer setting on a shot-by-shot basis. The files contain the following keys: ['Ebeam_energy_MeV', 'Electron_orbit_probe_x', 'Electron_orbit_probe_y', 'Electron_orbit_pump_x', 'Electron_orbit_pump_y', 'Fiducial', 'Fit_quality', 'Gas_monitor_mJ', 'Group', 'N_electrons', 'Photon_energy_FEL_eV', 'Probe_energy_xtcav', 'Probe_pulse_energy_mJ', 'Probe_width_fs', 'Pump_energy_xtcav', 'Pump_pulse_energy_mJ', 'Pump_width_fs', 'TOF_CO_yield', 'TOF_Ne_yield', 'Time_delay_XTCAV'] Description of the individual entries is found in the supplementary materials of the publication. The following table assigns the time delay and measure electron kinetic energy for each dataset. Time delay Ek = 234eV Ek = 220eV Ek = 210eV 40fs Run_210 Run_212 Run_213 20fs Run_231 Run_236 Run_235 15fs Run_239 Run_242 Run_241 10fs Run_238 Run_233 Run_234 5fs Run_228 Run_226 Run_225 0 Run_221 Run_223 Run_224 -5fs Run_217 Run_219 Run_220