Depolarized dynamic light scattering (DDLS) data, fit routine & fitting results

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(1) 5CB calibration Scattered light intensities of 5CB were measured in the splaytwist and twistbend geometry. Recorded lag time versus g2-1 is saved for each measurement/angle in a .dat file. File structure: each measurement series for several scattering angles at the same sample position has its own file. The 1.dat is giving always the summary of the measurement series (note that the column headings might be shifted sometimes). The recorded data of the first angle in the measurement series is found in 10.dat and depending on the settings of the measurement series (angle steps and total range) the data of the corresponding next higher angle is recorded in 11.dat, ect. .. The sub-folder "processed" or "processed_v4 gives the results (graphs and fitting parameters) from fitting the data with a python script. The _fexp text files contain the results of the fitting to a single exponential, whereas the _dexp text files the ones from the fitting to a double exponential. The python code is found in "ana-lichtstreuung-v4.py" and is commented in detail. The excel sheet "5CB calibration" contains the calculation of the factor X´´. The blue parts are the given parameters. The purple parts are from the twistbend geometry and the red parts are from the splaytwist geometry. Note that due to taking refraction into account, the scattering angle had to be recalculated (from "teta(old)" to "teta(new)") and the extraordinary refractive index was used. The final values of X´´ (one value obtained from the splaytwist geometry, and one for the twistbend geometry) were averaged and marked in red.

(2) lyo LS data This file contains all the recorded scattered light intensities of the micellar nematic LLC measured in the splaytwist and twistbend geometry. The folders in the "splaytwist" or the "twistbend" folder are just labelled according to date. The file structure is the same as in the 5CB calibration files. The excel sheet "calculation of K´s and eta´s" summarizes the results. Again, the given parameters are in blue. The purple parts contain the calculation of the bend elastic constant K3 and the bend viscosity (marked in red). The red parts contain the calculation of the splay (K1) and twist elastic constant (K2) and the corresponding viscosities (marked in red). The Qti files contain the graphs of the amplitude ratios versus the respective angular functions and the graphs of the inverse relaxation times.