Theoretical study of the structure, electronic properties and intramolecular hydrogen bonding

الملخص EN

The theortical calculations for pyrocatechol with and without intramolecular hydrogen bonding (I, II and III) were performed by quantum chemical methods.

The optimized structures of the compounds(I,II and III) were obtained by using the Density functional theory (DFT /Slater) level of theory using the basis set 6- 311G(d,p).

Study Showed that the value of total energy for form (II) is less than compounds (I and III), which strongly indicates the stability of form(II).

Also the dipole moment of form (II) is high compare with the forms (I and III).

The calculation also shows a decrease in the length of hydrogen bond in form (II) compare with that of form (III).

The thermodynamic calculation were carried out for (I,II andIII)and showed that favorable state is form (II)( more stable).