Update README.md

README.md

@@ -32,7 +32,7 @@ This app is designed for researchers, students, and enthusiasts who are interest
 **(5) Photoionization Database App**: Extract the binding energy spectrum, photoionization cross-sections, and photoionization asymmetry parameters of all elements between 1-118 with our powerful app. Easily identify the best core-levels to probe by finding the maximum cross-sections and gain a comprehensive overview of the core-level spectra of all elements! Accessible in MATLAB via the MatBase Main Menu, or explicitely by typing 'App_MatBase_Photoionization'.
 ![App_Photoionization](MatBase-v1.0.1/0_ReadMeImages/App_Photoionization.png)  
 
-**(6) N-Layer PES Intensity Model App**: Create a sample stack of N layers with different materials and thicknesses from the Materials Properties Database. Then, use the Photoionisation Cross-Section and Asymmetry Database to get the core-levels, cross-sections, and asymmetry parameters for each layer. The PES intensities for each layer are then determined using the Beer-Lambert law, considering the experimental geometry. This will help you compare XPS depth profile data (spectral intensity versus photon energy or emission angle), and determine the layer thicknesses in your samples from XPS! Accessible in MATLAB via the MatBase Main Menu, or explicitely by typing 'App_MatBase_NLayerPESIntensities'.
+**(6) N-Layer PES Intensity Model App**: Create a sample stack of N layers with different materials and thicknesses from the Materials Properties Database. Then, use the Photoionisation Cross-Section and Asymmetry Database to get the core-levels, cross-sections, and asymmetry parameters for each layer. The PES intensities for each layer are then determined using the Beer-Lambert law, modulated by the electron inelastic mean free path calculated using the TPP-2M formalism whilst considering the experimental geometry. This will help you compare XPS depth profile data (spectral intensity versus photon energy or emission angle), and determine the layer thicknesses in your samples from XPS! Accessible in MATLAB via the MatBase Main Menu, or explicitely by typing 'App_MatBase_NLayerPESIntensities'.
 ![App_NLayerPESIntensities](MatBase-v1.0.1/0_ReadMeImages/App_NLayerPESIntensities.png)