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    Experimental and Theoretical Investigations on Quadratic and Cubic Optical Nonlinearities of Cu(II), Co(II), Cd(II), Hg(II), Mn(II), and Zn(II) Transition Metal Coordination Complexes
    (Amer Chemical Soc, 2023) Belahlou, Hadjer; Karakas, Asli; Waszkowska, Karolina; Gozutok, Aysun; Karakaya, Mustafa; Guergouri, Mounia; Bouraiou, Abdelmalek
    A seriesof Cu(II), Co(II), Cd(II), Hg(II), Mn(II), and Zn(II)complexes (1-6) of (1-methyl-1H-imidazol-2-yl)(phenyl)methanone ligand (L) have been prepared and structurally characterized using single-crystalX-ray diffraction. A study of electrochemical properties has beenconducted by cyclic voltammetry. Transition metal coordination complexesare known to have promising optical nonlinearity behavior. So, toexplore the quadratic and cubic nonlinear optical (NLO) phenomenaof title transition metal coordination structures, several experimentaland theoretical investigations have been introduced, and their resultshave been evaluated. The second-harmonic generation (SHG) and third-harmonicgeneration (THG) techniques by means of the Maker fringe setup havebeen performed to analyze and evaluate the quadratic (& chi;((2))) and cubic (& chi;((3))) susceptibilities onthin films of 1-6 at 1064 nm. The maximum one-photonabsorption (OPA) wavelengths (& lambda;(max)) of 1-6 have been measured utilizing UV-visspectral analysis. To acquire the electric dipole moment (& mu;),static dipole polarizability (& alpha;), and first hyperpolarizability(& beta;) values of 1-6, we have taken advantageof the density functional theory (DFT) at the B3LYP level. The time-dependentHartree-Fock (TDHF) that is known as a very productive quantummechanical procedure has been chosen to achieve the static secondhyperpolarizabilities (& gamma;) and dynamic & alpha;, & beta;, & gamma;,& chi;((2)), and & chi;((3)) for 1-6. The measured data on the & chi;((2)), & chi;((3)), and (& lambda;(max)) results for 1-6 have been confronted with their correspondingcalculated values from the TDHF approach and the configuration interaction(CI) method including all doubly occupied molecular orbitals (MOs).Our calculation results of microscopic dipole polarizabilities andhyperpolarizabilities for 1-6 havealso been crosschecked with similar structures given in the previousworks and outcomes of several reference samples. The second- and third-orderNLO efficiencies produced theoretically and experimentally of thetitle materials have been outlined, revealing that the complexes withclosed-shell electronic states have turned out increments of second-and third-order susceptibility responses. This work has also elucidatedthat the substitutions of metallic cations (Cu2+, Co2+, Cd2+, Hg2+, Mn2+, andZn(2+)) have created favorable impacts upon & chi;((2)) and & chi;((3)) conclusions. Furthermore, we have surveyedthe first and second frontier MOs and their energy gap values viaDFT. Structural characterization and linearand NLO characteristicsof a series of six transition metal coordination complexes. The SHGand THG measurements at 1064 nm have been performed to obtain second-and third-order NLO susceptibilities. To entirely comprehend the second-and third-order NLO phenomena, detailed density functional theoryand ab initio quantum mechanical calculations have also been effectuatedto acquire dispersion-free dipole polarizabilities, second- and third-orderhyperpolarizabilities, and susceptibilities for studied compounds.
  • [ X ]
    Öğe
    Spectroscopic and theoretical optical properties of indoleninyl-substituted dibenzotetraaza[14]annulenes
    (Wiley, 2020) Ramle, Abdul Q.; Karakas, Asli; Arof, Abdul K. M.; Karakaya, Mustafa; Taser, Mehmet; Gozutok, Aysun; Chin Fei, Chee
    Two new macrocyclic dibenzotetraaza[14]annulene (DBTAA) compounds with indolenine (5) and pyridoindolenine (6) moieties were synthesized and characterized by spectroscopy. Both DBTAAs exhibit strong UV-Vis absorption properties in the Soret band region. The theoretical second-order nonlinear optical property, electric dipole moment (mu), dispersion-free dipole polarizability (alpha) and first hyper-polarizability values were calculated by density functional theory and time dependent density functional theory. The ab-initio quantum mechanical calculation by time-dependent Hartree-Fock method was utilized to investigate the dynamic dipole polarizabilities, dynamic second-order, static, and dynamic third-order (gamma) hyper-polarizabilities of the DBTAAs. The configuration interaction technique of all doubly occupied molecular orbitals possesses theoretically defined single-photon absorption (OPA) specifications for the examined structures. The computed maximum OPA wavelengths on both macrocyclic compounds coincide with the preceding measurement outcomes.
  • [ X ]
    Öğe
    Synthesis, spectroscopic studies and quadratic nonlinear optical characterisation of methoxy and aldehyde-substituted calix[4]arene
    (Taylor & Francis Ltd, 2024) Gozutok, Aysun; Karakas, Asli; Yilmaz, Aydan; Ozkan, Seyda Cigdem; Karakaya, Mustafa
    5,17-Di-tert-butyl-11,23-diformyl-26,28-dimethoxycalix[4]arene-25,27-diol (1) has been synthesised, and then characterised via elemental analysis, X-ray diffraction and MALDI-TOF mass spectrometry analyses, and also FT-IR, Raman, H-1 NMR, C-13 NMR, UV-Vis spectral techniques. The density-functional theory (DFT) has been utilised to calculate the electric dipole moment (mu), dispersion-free dipole polarisability (alpha) and second-order hyperpolarisability (beta) values for 1. The maximum one-photon absorption, vibrational frequency and NMR chemical shift descriptions of 1 have been also evaluated employing computational chemistry. Both simulated and also measured UV-Vis, vibrational, NMR spectra for title calix[4]arene have been introduced. Additionally, the conclusions of observed and simulated spectra have been evaluated together so as to assert the accordance among them. It has been ascertained that the examined material has reasonably great quadratic hyperpolarisability, indicating quite well second-order optical nonlinearity behaviour. The highest occupied molecular orbitals (HOMOs), the lowest unoccupied molecular orbitals (LUMOs) and HOMO-LUMO energy gaps of title structure have been appreciated from DFT. [GRAPHICS] .