Possibility of Complexation of the Calix[4]Arene Molecule with the Polluting Gases: DFT and NCI-RDG Theory

The calix[4]arenes (abbreviated as CX[4]) are characterized by a specific hydrophobic cavity formed by a four cyclically phenol groups to encapsulate a gas or small molecules. Recently, the CX[4] molecule is used in a specific media and in pharmaceutical drug delivery. The pollution problem will be a vital subject in the future because the increase of the explosions of the gaseous pollutants in the environment. In this report, we have encapsulated the polluting gases NO3, NO2, CO2 and N2 by the calix[4]arene molecule. In this work, The binding energies of the CX[4]-gas has been calculated including the BSSE (Basis Set Superposition Error) counterpoise (CP). The red-shift of the O-H bonding interactions obtained by adding the gas in the sensitive area of calix[4]arene is clearly explained by the infrared spectrum analysis. The Molecular electrostatic potential (MEP) of the stable CX[4]-gas complexes have been investigated in the endo-vs. exo-cavity regions. Finally, the non-covalent interactions analyses of the stable host-guests complexes have been estimated by using DFT calculations

Ab initio study of spectroscopic properties of the calcium hydride molecular ion

International audienceIn the present work, all adiabatic potential energy curves, spectroscopic constants and dipole moments of CaH+ molecular ion dissociating below the ionic limit Ca2+H− are presented. These curves are determined by an ab initio approach involving a non-empirical pseudo-potential for the Ca core, core-valence correlation accounted in operator form with two types of core polarization potentials (CPP) and full valence Configuration Interaction. The molecule is thus treated as a two-electron system. The potential energy curves and the spectroscopic constants are presented. In addition, the permanent and transition dipole moments are calculated for most of the states and reveal the underlying ionic states. A rather good agreement with the available theoretical works in the literature is obtained for the spectroscopic constants of the lowest states of the CaH+ molecule

DFT Calculations and Molecular Docking Studies on a Chromene Derivative

Chromenes and their derivatives have been considered as an important class of oxygen-containing heterocycles. There has been an increasing interest in the study of chromenes due to their biological activity. Herein, the structural, electronic, and vibrational properties of a chromene derivative, entitled 2‐amino‐5‐oxo‐4‐phenyl‐4,5‐dihydropyrano[3,2‐c]chromene‐3‐carbonitrile and abbreviated as Chrom-D, have been reported. The FT-IR, UV-vis, and 1H-NMR and 13C-NMR chemical shifts’ measurements were recorded. The molecular geometry and the vibrational frequencies are computed in the frame of density functional theory at the B3LYP/6-311++G(d,p) level of theory. The noncovalent interactions in the crystal lattice which are responsible to the 3D crystal structure of Chrom-D are investigated based on Hirshfeld surfaces and topological reduced density gradient (RDG) analysis. Molecular electrostatic potential surface, Mulliken charges, and Fukui functions are computed in order to find out the electrophilic and nucleophilic sites. The electronic properties of the title compound have been studied based on the TD-DFT calculations. Finally, Chrom-D has been evaluated as a multifunctional agent against Alzheimer’s disease (AD)

Theoretical investigation of the electronic properties of alkali atoms interacting with helium rare gas using a pseudopotential approach

International audienc