The gross atomic charges at various position in methyl-4acetoxybenzothiophene-6-carboxylate and 4-hydroxybenzothiophene-6-carboxylic acid were calculated by the parametric quantum mechanical molecular model AMI and PM3, based on neglect of diatomic differential overlap approximations. These data were correlated with H-1 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.