A structural study of diclofenac acid was carried out by density functional theory (DFT) calculations. Five different structures were found to corresponding its minimum energy conformations. Among several interconvertible rotations, the five most stable structures were studied and the intramolecular interactions governing the corresponding conformational preferences were considered and energy v...

In this present paper, we have made an attempt to explain the theoretical basis for the empirical hardness/softness concepts to address the reactivity of molecular complexes in a semi-quantitative way within the framework of density functional theory. A model based on local hard-soft-acid-base principle has been proposed. The results obtained using some prototype charge transfer complexes, Lewi...

This article discusses some ideas concerning an ‘average-pair-density functional theory’, in which the ground-state energy of a many-electron system is rewritten as a functional of the spherically and system-averaged pair density. These ideas are further clarified with simple physical examples. Then it is shown that the proposed formalism can be combined with density functional theory to build ...

A brief perspective of the development of the density functional theory of chemical reactivity since the identification of the chemical potential with the electronegativity in 1978 is presented. The reactivity concepts are examined together with the chemical principles associated with them. Then, the interaction energy between a nucleophile and an electrophile is analyzed in order to illustrate...

In this article, the complexes [Rh(Binor-S )(PR3)][BAr4] (R iPr, Cy, C5H9) are described. A combination of x-ray crystallography, NMR spectroscopy, density functional theory, and ‘‘atoms in molecules’’ calculations unequivocally demonstrates that the complexes contain rare examples of metal C–C agostic interactions. Moreover, they are fluxional on the NMR time scale, undergoing rapid and revers...

Combining density-functional theory calculations with many-body Green’s-function technique, we reveal that the macroscopic magnetization in half-metallic antiferromagnets does not vanish at finite temperature as for the T=0 limit. This anomalous behavior stems from the inequivalent magnetic sublattices which lead to different intrasublattice exchange interactions. As a consequence, the spin flu...

Bioactive molecules are playing essential role in the field of drug discovery and various pharmaceutical applications. Vibrational spectral investigations of the anti-Candida agent ({[(1E)-3-(1H-imidazol-1-yl)-1-phenylpropylidene]amino}oxy)(4-methylphenyl)methanone ((1E)-IPMM) have been recorded and analyzed to understand its structural geometry, interand intra-molecular interactions. The equil...

The Ohta-Kawasaki density functional theory of diblock copolymers gives rise to a nonlocal free boundary problem. Under a proper condition between the block composition fraction and the nonlocal interaction parameter, a pattern of a single droplet is proved to exist in a general planar domain. A smaller parameter range is identified where the droplet solution is stable. The droplet is a set whi...

Molecular simulation studies of chemical equilibrium for several reactions in pores of slit-like and cylindrical geometry have shown a significant effect of the confinement on the equilibrium compositions, with differences of several orders of magnitude with respect to the bulk fluid phase in some cases. As a first step towards the calculation of rate constants in confinement, we have studied t...

The Ohta-Kawasaki density functional theory of diblock copolymers gives rise to a nonlocal free boundary problem. In a proper range of the block composition parameter and the nonlocal interaction parameter, an equilibrium pattern of many droplets exists in a general planar domain. A sub-range of the parameters is identified where the multiple droplet pattern is stable. This stable droplet patte...