Density functional theory of the chemical potential of atoms and its relation to electrostatic potentials and bonding distances

THERMODYNAMIC AND REACTIVITY ASPECT OF β-CYCLODEXTRINE INCLUSION COMPLEXES WITH COUMARIN DERIVATIVES

“…In the same way, it can be observed from the chemical potential, specifically the negative value of this (eq. 7), that the tendency of attracting electron density is consistent with the Electrophilicity values, being a parameter that is also able to describe the antioxidant capacity by SET mechanism [21,23,24,25,26]. The electronegativity values increase in each ligand when the inclusion complex is formed (as well as the Electrophilicity), being C1 the one with the highest electronegativity value.…”

“…The non-covalent interactions that are generated between the ligands and the βCD cavity can be modeled and described through a second-order perturbative analysis (E2PERT) [17,18] which describes the interactions between Lewis (donor) and Non-Lewis (acceptor) type natural bond orbitals (NBO) [19] of the βCD/coumarin system, in addition to an electron density mapping that allows describing the types of non-covalent interactions [20].The main antioxidant mechanisms (AOX) are SET mechanisms (one electron transfer mechanism) which is described as the ability to neutralize a free radical when it yields an electron to an electroacceptor species, mainly molecular species presenting rings with resonant 𝜋 electrons [21], and HAT mechanisms (one hydrogen atom transfer) which neutralizes free radicals when it yields labile hydrogens from a homolytic radical cleavage [22]. The SET and HAT mechanisms are related to the global and local reactivity indices, the SET mechanism being described by the chemical potential (𝜇) [23] and the Electrophilicity (𝜔) [24,25,26], while the HAT mechanism is described by the Fukui functions (𝑓 (𝑟) ) [27] and the Dual Descriptor (𝑓 (2) ) [28] The present study aims to model and describe the chemical reactivity of a series of coumarin derivatives and how they form inclusion complexes with β-Cyclodextrin.…”