The gross atomic charges at various position in methyl-4- acetoxybenzothiophene-6-carboxylate and 4-hydroxybenzothiophene-6-carboxylic acid were calculated by the parametric quantum mechanical molecular model AM1 and PM3, based on neglect of diatomic differential overlap approximations. These data were correlated with 1H NMR chemical shifts of the present molecules. Thermodynamic functions, namely, heats of formation, enthalpy and entropy of these molecules also calculated in the temperature range 100-1000 K were reported. © 2021 Elsevier B.V., All rights reserved.