Ensity Functional Reactivity Theory Studies Of Inter-molecular Systems With Weak Interactions

Intermolecular interactions are called weak interaction, is a hot topic field of chemistry. Many people are concerned about it. In this paper, we studied molecular interactions between systems, including hydrogen, halogen bond and cation-π interaction system. Within the framework of density functional activity theory (DFT) and density functional theory activity (DFRT).Hydrogen bonding system by using density functional theory (DFT) activity and density functional theory (DFRT) and two energy decomposition method (EDA) for the stability of the water clusters. In this work, we use quantum molecular dynamics to generate a large number of conformations for octamer water clusters and then employ two energy partition schemes from density functional theory to pinpoint the principles governing the stability of these species. We found that their relative stability is decidedly correlated with the steric repulsion and exchange-correlation interactions. Two independent explanations using two different quantities are subsequently proposed to account for their relative stability. This work sheds light to the fundamental understanding about the origin and nature of molecular conformational stability for systems like water clusters as well as other systems in general.Based on density functional theory(DFT) to study cation-π interaction. Benzene derivatives and tetramethylammonium formed with compounds showing stronger attraction. And electron donating groups have the ability to strengthen the interaction between the cation and the aromatic system. We found that their Total Energy difference is decidedly correlated with the steric repulsion and exchange-correlation interactions. Two independent explanations using two different quantities are subsequently proposed to account for their Total Energy difference. This work studied the origin and nature of molecular conformational stability for systems like tetramethylammonium and aromatic system.Many people focus Halogen bond. There are a large number of experimental and theoretical researched. But little people attention the bifurcated halogen bonds. It play a important role in crystal assemble. It’s necessary for us to study. In this work, we use four molecules, RX (X Cl, Br, R is H and CH3), and CH3NO2form with complex, respectively. Using density function theory (DFT), density function reactively theory and non-covalent interaction analysis to research the energy properties and structure properties. We found that bifurcated halogen bonds compared with two center complex more actively and stability. The compound have bromine atom have stronger interaction than the chlorine atom-containing compound. Two oxygen atoms with the halogen atom trend to ring.