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Light diffusing polycarbonate samples were exposed to protons fluences at levels between 10 11 and 10 16 p/cm 2 .T he variation of the refractive index and color intensity with the proton fluence has been studied. The results show that the polycarbonate samples acquire color changes under proton irradiation. Furthermore, thermogravimetric analysis has been performed. It was found that both the onset temperature and activation energy of thermal decomposition are affected by the proton fluencies owing to the degradation and crosslinking processes. Moreover, structural property studies using X-ray diffraction, intrinsic viscosity and Fourier transform infrared spectroscopy were performed.

Ab initio atomistic thermodynamics adapted using density functional theory and to study the effect of Bromine (Br) chemisorption on the Cu(001) surface is with coverage (0.11, 0.25, 0.5, 0.75 and 1) ML. H site with coverage of 0.25ML is the most preferred site followed by B site with the order of stability of (H > B > T). The majority of Br atoms stable at B site. Significant structural changes are observed for the first layer’s Cu atoms. For instance, for the bridge (B) site with coverage \(\ge 0.5\)ML, one of the Cu atoms moves from first to second layer, For the hollow H(0.75 and 1) ML and H(0.75 and 1) ML configurations; two Br’s layers thin film are produced on the top of the slab. The substitutional adsorption modes are stable for coverages from 0.25ML up to 2ML. Under ultrahigh-vacuum conditions, the free energies of different Br/Cu(110) structures as a function of Bromine chemical potential are calculated, these calculated energies showed that the bridge site is the most stable for coverages of 1/9ML, whereas the bridge and hollow configurations are the most stable at 1/4ML coverage. Thermodynamics insights provided herein shall be instrumental to underpin bromine interaction with Cu surfaces in applications related to environmental chemistry as in the thermal recycling of e-waste.

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