Saleh Mohammad

Photodetachment of Di-atomic Negative Ion H 2 − near a Surface

We describe the effects of plane surface on the photo-detached electron spectra from H−2. A z-polarized laser is used for the detachment of electrons. The detached electron flux and photodetachment cross section are derived. There exists strong dependence on the distance of the H−2 from the surface and also on the separation of atomic centers of H−2. The results show strong oscillations for smaller values of distances, whereas for larger values the oscillating structure disappears.

Detached Electron Spectra from H− near a Partially Reflecting Spherical Surface

The photodetachment of a hydrogen negative ion (H−) near a partially reflecting surface with a spherical shape is investigated by a theoretical imaging method. Analytical expressions for the detached electron flux and total photodetachment cross section are derived. It is found that two parameters, i.e. curvature radius rc and reflection parameter K, control the photodetachment spectra. Furthermore, these parameters can be used for the classification, identification and revelation of minor details like curvature of different types of surfaces.

First Principle Calculations of the Ground and Excited State Properties of RbPbF3

Structural, elastic, electronic, chemical bonding and optical properties of the cubic RbPbF3 compound under pressure are studied using a highly accurate state-of-the-art full potential linearized augmented plane wave method. The exchange correlation effects are included through the generalized gradient and modified Becke—Johnson exchange potential. The lattice constant and band gap of the cubic RbPbF3 decreases with enhanced pressure. RbPbF3 is brittle, elastically anisotropic, and a direct bandgap material. Its optical properties such as refractive index n(ω), extinction coefficient k(ω), reflectivity R(ω), and optical conductivity σ(ω) are predicted.

Study of low doses cisplatin synergistic effect on photodynamic outcome of aluminum phythalocyanine on soft tissue sarcoma (RD) cell line

Photodynamic therapy (PDT) in combination with other treatment modality expects to overcome the drug resistance experienced in monotherapy. In this present work combination of chemo cum PDT is studied over the range of doses. It is found that treating cells/exposing cells to chemo drug (cisplatin, CDDP) and PDT individually results in minimal cell killing (∼7% and ∼16%) compared to the administration of chemo followed by PDT (∼50% cells were viable). These results showed that cell viability synergistically decreases in case of combination treatment as compared with individual treatment. Photodynamic therapy (PDT) in combination with CDDP chemotherapy expects to overcome the drug resistance experienced in monotherapy.