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In this study, ZnO was doped with 0.01% Mn and it is grown on p-Si by the sol-gel spin-coating method. Obtained the thin film was studied that to understand the effect of 0.01% Mn-doping ratio on the optical and electrical properties of ZnO structure. In this context, first, the morphological structure of the thin film was studied with the use of atomic force microscopy (AFM). The surface structure was obtained homogeneous, and roughness and fiber size were calculated between 27.2-33.6 and 0.595-0.673 nm, respectively. Second, the optical properties were characterized via ultravioletvisible (UV-Vis) spectrophotometry. Third, the effect of light intensity on junction properties of the photodiode was studied. The current-voltage (I-V) of the photodiode was measured under dark and at the different intensities of illumination. Obtained results showed that the current of photodiode was increased with the intensity of illumination from 6.41 9 10 -7 to 5.32 9 10 -4 A. These results indicate that photocurrent under illumination is higher than the dark current. After that, the other parameters of the photodiode such as barrier height and ideality factor were determined from forwarding I-V plots using the thermionic emission model that the barrier height and the ideality factor were found 0.74 eV and 5.3, respectively. On the other hand, the capacitance-voltage (C-V) was measured at the different frequencies. The C-V characteristic shown that C-V characteristic of the photodiode was changed depends on increasing frequency. In addition, the interface density (D it ) value was decreased by increasing frequency too. Similarly, the serial resistance of the photodiode was also decreased by increasing frequency. Received all these results indicated that Mn-doped ZnO thin film sensitive to light and due to this property, it can be used for different optoelectronic applications as a photodiode and photosensor.

Using variational Monte Carlo method, we calculated the 1 1 0 + state energies, the derivatives of the total energy and the ionisation energies of the helium atom, and hydrogen negative ion in the presence of magnetic eld regime between 0 a.u. and 10 a.u. Our calculations are based on using two types of compact and accurate trial wave functions used before to calculate energies in the absence of magnetic eld. Our results are in good agreement with the most recent previous accurate values and also with the exact values.

The variational Monte Carlo method is used to evaluate the ground-state energy of the confined hydrogen molecule, . Accordingly, we considered the case of hydrogen molecule confined by a hard prolate spheroidal cavity when the nuclear positions are clamped at the foci (on-focus case). Also, the case of off-focus nuclei in which the two nuclei are not clamped to the foci is studied. This case provides flexibility for the treatment of the molecular properties by selecting an arbitrary size and shape of the confining spheroidal box. An accurate trial wave function depending on many variational parameters is used for this purpose. The obtained results are in good agreement with the most recent results.

AbsractBy Using the variational Monte Carlo (VMC) method, we calculate the 1 state energies, the dissociation energies and the binding energies of the hydrogen molecule and its molecular ion in the presence of an aligned magnetic field regime between 0 . . and 10 . . The present calculations are based on using two types of compact and accurate trial wave functions, which are put forward for consideration in calculating energies in the absence of magnetic field. The obtained results are compared with the most recent accurate values. We conclude that the applications of VMC method can be extended successfully to cover the case of molecules under the effect of the magnetic field.