Tutorial02

Fitting the complex refractive index by manual mode

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ComplexRI represents the spectra of complex refractive index by

$n({\tilde {\nu }})=\eta ({\tilde {\nu }})+i\kappa ({\tilde {\nu }})=n_{j}^{0}+\sum _{l=1}^{l_{max}}{\frac {A_{l}}{{\tilde {\nu }}_{l}-{\tilde {\nu }}-i\gamma _{l}}}$

and optimize the set of parameters $A_l$, $\nu_l$, $\gamma_l$ and $l_{max}$. Sometimes the fitting of these parameters is facilitated by giving the initial set of parameters.

In this tutorial, we will use the C-C-O asymmetric stretching region of ethanol as an example. The initial parameters in the fitting procedure are set by users.

The ATR-IR experimental data file in this tutorial can be downloaded Here. Use Ctrl + s to save the file in your local computer. The file name is “data_ethanol.txt”.

Then, please move to the Main Package page.

Upload the“data_ethanol.txt” in ① and set the other parameters according to the following figure. (For the meanings of each part, please refer to ➡Manual.)

Now, please click the “Execute Fitting” to start fitting.

Results of Tutorial02

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The Result should be like follows.

The meaning of each output can be found in ➡Manual

Tutorial01