Assessing the importance of Van der Waals interactions on the adsorption of azobenzene on the rutile TiO2(1Â 1Â 0) surface

► The effect of dispersion in the stability of the cis- and trans- azobenzene on TiO2(1 1 0) is analyzed. ► Dispersion terms are crucial to explain relative stability. ► Dispersion terms are crucial to describe the cleavage of the NN azo bond reaction energy. ► Dispersion terms do not affect the main qualitative features of the interaction.