Cyclohexanone-Based Chalcones as Alternatives for Fuel Additives.

The use of small molecules, such as chalcones and their derivatives, for more efficient fuels is in increasing demand due to environmental factors. Here, three crystal structures (BH I, II, and III) of cyclohexanone-based chalcones were synthesized and described by single-crystal X-ray diffraction and Hirshfeld surface analysis. The supramolecular modeling analysis on the hyperconjugative interaction energies and QTAIM analysis at the ωB97XD/6-311++G(d,p) level of theory were carried out to analyze the intermolecular interactions in the solid-state. The structure-property relationship, frontier molecular orbital, molecular electrostatic potential, and the experimental calorific value analysis show that the three compounds are a good alternative to be used as an additive for some fuels. Our findings represent a further step forward in the development of cheaper and more efficient fuel additives and pose an opportunity for further investigation on similar analogues.

A new isostructural halogenated chalcone with optical properties.

Chalcones are organic compounds that present a number of properties. This study presents a comprehensive structural description of a new derivative of a chlorine-substituted chalcone in comparison with a bromine chalcone. Also, supermolecule and sum-over-state approach were used to describe the optical properties of these structures regarding the substitution of the bromine by the chlorine atom. In addition, the electrical properties, dipole moment, linear polarizability, and second IDRI hyperpolarizability were calculated. The linear refractive index and the third-order nonlinear macroscopic susceptibility were evaluated as a function of the applied electric field frequency. Furthermore, the quantum mechanics calculations that were implemented at the M06-2X/6-311++G(d,p) level of the theory for these isostructural chalcones indicate that the change in halogen atoms does not cause meaningful changes in their conformation. Finally, we can postulate that side-to-side and the antiparallel interactions are the interaction forces that drive the crystal growth for new isostructural chalcones. The NLO properties showed title compounds that are good candidates for use as NLO materials.