CONTRIBUTION OF WEAK INTERMOLECULAR INTERACTIONS IN 3-ACETYL COUMARIN DERIVATIVES

Abstract

Normal 0 Analysis of the nature of intermolecular interactions is of utmost importance in the field of crystal engineering to facilitate the design of new materials with desirable properties. A better understanding of these interactions and their influence on the crystal packing can be obtained by evaluating the energetics associated with these interactions. In this regard, we have identified from the literature a series of 3-acetyl coumarin derivatives and calculated the lattice energy of these crystal structures by using PIXELC module in Coulomb London Pauli (CLP) package. The lattice energy of all the compouds have been partitioned into corresponding coulombic, polarization, dispersion and repulsion contributions. The important packing motifs have been extracted from the crystal packing for a complete understanding of the nature of intermolecular interactions with quantitative inputs from an evaluation of the interaction energy calculated from Pixel. It is found that most stabilizing molecular pair in most of the structures involve bifurcated C-H…O hydrogen bonding. The weak interactions like C-H…O, π…π and C-H…X ( Cl or Br) also play an important role in the stabilization of the crystal packing.