Atomic Force Microscopy (AFM) force spectroscopy data for the interfacial organization of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl) (C4mimNTf2) on mica, and Matlab data treatment codes for data curing and averaging the force-separation profiles

Description of raw_data_csv.zip: Atomic Force Microscopy (AFM) force spectroscopy data obtained with a JPK NanoWizard 4 AFM equiped with a fluid cell. Sample preparation and data acquisition were performed by Layla Bou Tannous. Substrate: cleaved Mica.Fluid: 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl) (C4mimNTf2).AFM probe: cantilever A from an OPUS 4XCNN probe (MikroMasch). The cantilever was fully immersed in the fluid. Cantilever spring constant: 0.25 +- 0.02 N/m. Sensitivity: S= 47.2 nm/V determined with contact-based-method from file "SensitivityCalibration_Approach_0.csv" Files "Approach_01.csv" to "Approach_50.csv" correspond to 50 successive approaches on the same spot, numbered in chronological order. Acquisition frequency: 2048 Hz Constant approach velocity: ~ 60 nm/s File structure: - column 1: time_second (time vector in seconds) - column 2: raw_deflection_U_volt (raw deflection vector in Volts) - column 3: smoothed_displacement_z_nanometer (measured piezo displacement vector in nanometers, smoothed by the JPK acquisition sofware) - column 4: raw_displacement_z_nanometer (measured piezo displacement vector in nanometers, raw data) Description of MatlabFunctions.zip: Matlab codes written by Audrey Steinberger (Matlab version R2023b): - DataCuring.m computes the corrected force matrix F [nN], deflection matrix d [nm], zero-separation vector z0 [nm], and separation matrix h [nm] from the 50 force spectroscopy approach data contained in the folder 'raw_data_csv. It also computes and displays the separation h 1D histogram, the F versus h 2D histogram, and four average force-separation profiles using the various functions provided in the same folder - compute_gradF_Fint_cumsum.m and compute_gradF_Fint_cumtrapz.m both compute the force gradient from the separation h histogram, then integrate it to recontruct the force profile (can be applied either on a single F vs h curve or on an ensemble of curves). Work only with a constant approach velocity. - ForceAverage_interp.m is a standard averaging scheme for quasi-static force spectroscopy data, based on interpolation over the piezo displacement vector. - Ymedian_on_Xbins.m computes the median force curve from any pair of X and Y matrices, from the sorting pattern of the histogram of the X matrix. - Hist2D_average.m computes the mean Y versus X curve from the bivariate histogram of X and Y. Further detailsabout the data aquisition and the Matlab functions are given in a preprint available on HAL: https://cnrs.hal.science/LPENSL/hal-05534087v1 and in the header of the functions.