Browsing by Author "Dalgic S."

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A comparative DFT study on Al- and Si- doped single-wall carbon nanotubes (SWCNTs) for Ribavirin drug sensing and detection
(2023-05-01) Dalgic S.S.; Al-Sawaff Z.H.; Dalgic S.; Kandemirli F.
In this work, we have presented a comparative study on Ribavirin (RBV) drug sensing and detection on the pristine and functionalized single-wall carbon nanotubes (f-SWCNTs) by Density Functional Theory (DFT) method. The pristine and metal-doped zigzag (4,0) and (6,0) SWCNTs were first considered for the RBV adsorption. All the probable positions of RBV adsorption were investigated to find which one is energetically favourable. The topology analysis of the Quantum theory of atoms in a molecule (QTAIM) with non-covalent interactions (NCI-RDG), Frontier molecular orbitals (FMO), Density of states (DOS), and non-linear optical (NLO) analysis were carried out to understand the molecular structure, electrical, electronic and optical properties of complexes. The charge analysis indicates that charge transfer is from the adsorbed RBV to the pristine and metal-doped (4,0) and (6,0) SWCNTs. The highest values of adsorption energies for Al-, Si-doped and pristine (4,0) SWCNTs were determined as −34.688, −87.999 and −10.382 kcal/mol, respectively, whereas corresponding values for metal-doped and pristine (6,0) SWCNTs are about −43.592, −20.661 and −12.414 kcal/mol, respectively. The results suggest that those bare and metal-doped (4,0) SWCNTs and (6,0) Si-SWCNTs can serve as promising sensors in practical applications to detect, recognize and carrier RBV drug for its medicinal drug delivery applications. Based on the NLO properties of (6,0) Si-SWCNTs and pristine (6,0) SWCNT (with an acceptable recovery time of 279s and first hyper polarizability value of β = 229.25 × 10−30 cm5 esu−1), those nanotubes may be possible candidates to be used as the optoelectronic sensor for RBV drug. The appropriate short length of nanotubes was obtained.
A DFT study on the size and defect induced properties of 2H-Au nano surface by small molecules adsorption
(2023-03-01) Sakarya A.; Senturk Dalgic S.; Dalgic S.; Kandemirli F.
The size effect and defect-related properties of the Au nanosurface in the hexagonal phase (Au2H) have been investigated by Density Functional Theory (DFT) using the adsorption of small molecules. The OH, H2O, H2O2, C2H5OH, H2 and O2 molecules were considered. The atomic H and O adsorption were also taken into account for comparison. The adsorption distances, energies, frontier molecular orbitals and density of state analysis of small molecules on top, bridge and hollow sites of the Au2H surfaces were computed in conjunction with charge distribution analysis. The size, dimension and phase-dependent adsorption energies were obtained by comparison with previous calculations. The complexes’ stability changes with the sites and interacting groups. Apart from H2O2 and C2H5OH on top site of Au2H, all studied groups’ adsorption shows exothermic character. The adsorption energies reveal the order O > OH > H > H2O> O2. The Au2H surface is most sensitive to H, O, OH and O2. Therefore, the Au2H can serve as a promising sensor to detect and recognize those atoms/molecules in practical applications. The Au2H also has potential applications as a work function-type sensor for H, OH and C2H5OH. The size limit of Au2H was defined.