sudarshanv01 / tpd-analyse

First order Temperature Programmed Desorption analysis package

TPD analysis for first order desorption process

Details

Calculate the adsorption energy, configurational entropy and adsorbate-adsorbate interaction parameter for first order desorption from TPD curves.

Equations used to fit are described in the manuscipt: How to Extract Adsorption Energies, Adsorbate-adsorbate Interaction Parameters, and Saturation Coverages from Temperature Programmed Desorption Experiments (link)

Installation

The package can be installed via

pip install tpd-analyse

Usage

All inputs must be passed to the central class PlotTPD. An example of some possible inputs are shown below.

    TPDClass = PlotTPD(exp_data=files,
                        order=order,
                        thermo_ads=vibration_energies_ads,
                        thermo_gas=vibration_energies_gas,
                        plot_temperature=np.linspace(100, 500, 50), 
                        T_switch=T_switch_211,
                        T_max=T_max_211,
                        T_rate_min=T_rate_min_211,
                        beta=beta_211)

1. exp_data: list of filenames. Each filename must be of the format exposure_<some_value>.csv where some_value can be the exposure in any units.
2. order: currently only first order desorption reactions are implemented, so order=1
3. thermo_ads (optional): Here the ase class HarmonicThermo can be passed with the required inputs for the adsorbate(s) of interest. More information about the class can be found here.
4. thermo_gas: Similar to the thermo_ads, only for gas molecules. One option is to use IdealGasThermo
5. plot_temperature: A temperature range that the equibirium coverage can be determined in. An example range would be `np.linspace(100, 500)
6. T_switch: Is there are more than one processes occuring in one TPD plot, supply a list of temperatures to switch from one to another in K.
7. T_max: Maximum temperature to consider for all the TPDs.
8. T_rate_min: Minimum temperature at which the baseline correction can be done.
9. beta: Heating rate in K/s
10. correct_background (optional): bool to decide if the background is corrected
11. p (optional): Pressure in the case of equilibirum, only useful if equilbirum coverages are needed
12. initial_guess_theta (optional): Initial guess for the coverage in the Newton root solver
13. guess_b(optional): Guess for the ads-ads interaction.
14. calculate_eq_coverage (oprtional): Decide is the equilibrium coverage is computed.