In this research work, the Hellmann potential is studied in the presence of external magnetic and AB-flux fields. We solve the Schrodinger in the presence of these fields and the potential via the functional analysis approach (FAA). The energy equation and wave function of the system are obtained in closed form. The effect of the fields on the energy spectra of the system examined in details. It is found that the AB field performs better than the magnetic in its ability to remove degeneracy. Furthermore, the magnetization and magnetic susceptibility of the system was discussed at zero and finite temperatures. We evaluate the partition function and use it to evaluate other thermodynamic properties of the system such as magnetic susceptibility,

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In this investigation, the feasibility of detecting the amantadine (AMD) molecule onto the outer surface of pristine fullerene (C[Formula: see text]), as well as C[Formula: see text]X ([Formula: see text], Ge, B, Al, Ga, N, P, and As) decorated structures, was carefully evaluated. For achieving this goal, a density functional theory level of study using the HSEH1PBE functional together with a 6-311G(d) basis set has been used. Subsequently, the B3LYP-D3, wB97XD and M062X functionals with a 6-311G(d) basis set were also employed to consider the single point energies. Natural bond orbital (NBO) and the quantum theory of atoms in molecules (QTAIM) were implemented using the B3LYP-D3/6-311G(d) method and the results were compatible with the electronic properties. In this regard, the total density of states (TDOSs), the Wiberg bond index (WBI), natural charge, natural electron configuration, donor–acceptor NBO interactions, and the second-order perturbation energies are performed to explore the nature of the intermolecular interactions. All of the energy calculations and population analyses denote that by adsorbing of the AMD molecule onto the surface of the considered nanostructures, the intermolecular interactions are of the type of strong physical adsorption. Among the doped fullerenes, Ge-doped structure has very high adsorption energy compared to other elements. Generally, it was revealed that the sensitivity of the adsorption will be increased when the AMD molecule interacts with the decorated fullerenes and decrease the HOMO–LUMO band gap; therefore, the change of electronic properties can be used to design suitable nanocarrier.

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In recent years, there has been a large amount of attention focused on the design of filtering antennas to reduce the front-end size of modern wireless communication systems. Although numerous design approaches are presented in the literature, they are usually applicable to a certain microwave circuit structure. Additionally, their implementations demand extra matching circuits or a structure which leads to an increase in the filtering antenna size. In this paper, the design of a 3rd-order filtering antenna operating at the X-band frequencies is presented utilizing the coupling matrix approach. It is based on 3rd order coupled-resonators filter without employing any extra structure. For the physical configuration, three inline coupled rectangular waveguide cavity resonators operating at TE 101 mode are employed. The output of the last resonator is coupled to free space via a rectangular aperture. The dimensions of the aperture are manipulated to control the radiation quality factor (Q r ). To validate the simulated results, the design has been fabricated using the Computer Numerical Control technique. Excellent agreement between the simulation and measurement results has been obtained. The fractional bandwidth (FBW) is more than 10% when the reflection coefficient S 11 = −20 dB. The gain response is very flat (7.54 ±0.2 dBi) from 9.5 to 10.5 GHz. The proposed filtering antenna is compact and low profile which may be of interest in radar applications.aperture antenna, coupling matrix theory, filtering antennas, waveguide cavity resonators | INTRODUCTIONRecently, integrations among the front-end components of wireless communication systems have become more popular, particularly among bandpass filters (BPFs) and antennas (so-called filtering antennas). [1][2][3][4] Such integration not only introduces filtering functionality to the antenna, but also reduces the losses and the front-end size of the system. 5 Numerous approaches have been presented in the literature to enhance the bandwidth (BW) of the filtering antennas so as to increase the data rate capability and reduce spurious signals.