The Ultraviolet-visible (UV-Vis) spectra indicate that anthracenyl chalcones (ACs) have high maximum wavelengths and good transparency windows for optical applications and are suitable for optoelectronic applications owing to their HOMO–LUMO energy gaps (2.93 and 2.76 eV). Different donor substituents on the AC affect their dipole moments and nonlinear optical (NLO) responses. The positive, negative, and neutral electrostatic potential regions of the molecules were identified using molecular electrostatic potential (MEP). The stability of the molecule on account of hyperconjugative interactions and accompanying charge delocalization was analyzed using natural bond orbital (NBO) analysis. Open and closed aperture Z-scans were performed using a continuous-wave frequency-doubled diode-pumped solid-state (DPSS) laser to measure the nonlinear absorption and nonlinear refractive index coefficients, respectively. The valley-to-peak profile of AC indicated a negative nonlinear refractive index coefficient. The obtained single crystals possess reverse saturation absorption due to excited-state absorption. The structural and nonlinear optical properties of the molecules have been discussed, along with the role of anthracene substitution for enhancing the nonlinear optical properties. The calculated third-order susceptibility value was 1.10 x10-4 esu at an intensity of 4.1 kW/cm2, higher than the reported values for related chalcone derivatives. The NLO response for both ACs offers excellent potential in optical switching and limiting applications.
Two organometallic compounds known as (E)-1-ferrocenyl-(3-fluorophenyl)prop-2-en-1-one (Fc1) and (E)-1-ferrocenyl-(3-fluoro-4-methoxyphenyl)prop-2-en-1-one (Fc2) are designed and synthesized for application in dye-sensitized solar cell (DSSC) based on a donor-π-acceptor (D-π-A) architecture. By strategically introducing a methoxy group into the acceptor side of the compound, Fc2 which has adopted a D-π-A-AD structure are compared with the basic D-π-A structure of Fc1. Both compounds were characterized by utilizing the IR, NMR and UV-Vis methods. Target compounds were further investigated by X-ray analysis and studied computationally using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) approaches to explore their potential performances in DSSCs. An additional methoxy group has been proven in enhancing intramolecular charge transfer (ICT) by improving the planarity of Fc2 backbone. This good electronic communication leads to higher HOMO energy level, larger dipole moment and better short-circuit current density (Jsc) values. Eventually, the presence of methoxy group in Fc2 has improved the conversion efficiency as in comparison to Fc1 under the same conditions.
1 December 2021 in Journal of Solid State Chemistry
Two newly halogenated chalcones, derivatives of C15H10ClFO (CH-ClF) and C15H10F2O (CH-FF), were synthesized using the Claisen–Schmidt condensation method. Both compounds were crystallized using a slow evaporation method, forming a monoclinic crystal system with a space group of P21 and P21/c, respectively. The compounds were further analyzed using spectroscopic techniques such as Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (NMR), and Ultraviolet–Visible (UV–vis) analyses. The single crystal X-ray diffraction method revealed the existence of C−H⋯O and C−H⋯F intermolecular interactions in CH-FF. Hirshfeld surface analysis was performed to confirm the existence of intermolecular interactions in the compounds. The molecular geometries obtained from the X-ray structure determination were further used to optimize the structures using density functional theory (DFT), with the B3LYP/6-311G++(d,p) basis set in the ground state. The TD-DFT/B3LYP method was used to obtain the electronic properties and the HOMO–LUMO energy gap. Both compounds exhibited A-π-A architecture with different halogen substituents in which the CH-FF, containing -fluoro substituents, possessed good electron injection ability due to its electronegative properties. This increased the flow of the charge transfer for the dye regeneration process and enhanced the efficiency of the dye-sensitized solar cell (DSSC).
26 May 2021 in Bioinorganic Chemistry and Applications
This article presents both experimental and computational study of a new Ni(II) complex, namely, bis{2-(2-trifluoromethylbenzylidene)hydrazine-1-carbothioamido-κ2N2, S}nickel(II) (abbreviate as NiL2). The complex was synthesized and well characterized using various spectroscopic methods. The single X-ray crystallographic study revealed a distorted square planar geometry around Ni(II) metal ion centre in which the angles deviated from ideal 90° with a maximum value of 6.57° occupied by nitrogen and sulphur donor atoms. The theoretical bond lengths and angles for the NiL2 complex were obtained by using the B3LYP level of density function theory (DFT) with LANL2DZ/6-311G (d, p) basis sets. These results showed very good agreement with the experimental X-ray values. The electrophilicity index (ω=50.233eV) shows that the NiL2 complex is a very strong electrophile. In addition, strong FH/HF interactions with 28.5 of the total Hirshfeld surface analyses in NiL2 were obtained indicating that the complex could bind with protein effectively. Furthermore, the new NiL2 complex was docked with plasma retinol-binding protein 4 (RBP4) (PDB id: 5NU7), which implied that the NiL2 complex bound to Tyrosine 133 and Aspartate 102 amino acids via N-H intermolecular hydrogen bonds.
4 May 2018 in Acta Crystallographica Section E Crystallographic Communications
The molecular and crystal structure of two new chalcone derivatives, (E)-1-(anthracen-9-yl)-3-[4-(piperidin-1-yl)phenyl]prop-2-en-1-one, C28H25NO, (I), and (E)-1-(anthracen-9-yl)-3-[4-(diphenylamino)phenyl]prop-2-en-1-one, C35H25NO, (II), with the fused-ring system at the same position are described. In the crystals of (I) and (II), the molecules are linked via C—H...O hydrogen bonds into inversion dimers, forming R22(22) and R22(14) ring motifs, respectively. Weak intermolecular C—H...π interactions further help to stabilize the crystal structure, forming a two-dimensional architecture. The molecular structures are optimized using density functional theory (DFT) at B3LYP/6–311 G++(d,p) level and compared with the experimental results. The smallest HOMO–LUMO energy gaps of (I) (exp . 2.76 eV and DFT 3.40 eV) and (II) (exp . 2.70 eV and DFT 3.28 eV) indicates the suitability of these crystals in optoelectronic applications. All intermolecular contacts and weaker contributions involved in the supramolecular stabilization are investigated using Hirshfeld surface analysis. The molecular electrostatic potential (MEP) further identifies the positive, negative and neutral electrostatic potential regions of the molecules.