Modelagem Molecular, Parâmetros de Reatividade, Estudos Térmicos, Condutimétricos e Espectroquímicos do Ácido Cítrico Para Utilização na Síntese de Sistemas Metálicos Complexos

Abstract

Citric acid is a tricarboxylic organic compound with the potential to facilitate aqueous interactions with metal ions, thereby generating possible biodisponibility and probable absorption at biological sites requiring these essential metals. Additionally, it holds promise as a potential cathodic protective buffering layer, aiming to enhance the efficiency of organic solar cells. In this study, we conducted molecular modeling, assessing molecular parameters such as bond angles and lengths, atomic Coulombic potential, molecule stereochemistry, reactivity parameter calculations, recording thermogravimetric curves, measuring molar conductance, and recording and analyzing infrared and UV-visible spectra to determine the oscillator strength and dipole moment of the compound. Through the employed techniques, we evaluated the thermal and photochemical stability of this species, which holds potential applications as electron transfer systems in light converters, radiation emitters, and light-to-electricity conversion devices. The molecular modeling study indicated that atoms O(5) and O(1)/O(7) exhibited a negative charge density and appreciable parameters, along with atoms O(3), O(2)/O(6), and O(4). pH and conductometry analyses, 3.39 and 211.91 S cm-2 mol-1, respectively, demonstrated that even though the compound undergoes three dissociations, observable characteristics of a well-defined 2:1 or 1:2 compound were confirmed by the measured conductance. The infrared spectrum exhibited crucial peaks in the region of 1743 and 1699 cm-1, indicative of C=O bonds and the O-H-O group at 3493 and 3287 cm-1, respectively. In the UV-Vis spectrum, a band in the intervening region 948,6 – 999,4 nm, where the oscillator strength for this electronic transition measured 2.4 and 2.2 × 10-5, according to the Drago and Figgs methods, respectively. The transition dipole moment was determined to be 0.070 and 0.067 Debye using the Drago and Figgs methods, respectively.