The non-coincidence effect in binary mixtures: is a sign inversion with dilution fake or reality?

This study investigates whether benzene may be effective in promoting the s ign inversion of the non-coincidence effect of the carbonyl stretching mode , nu (3)(C=O), of acetone in the high dilution regime, as claimed in litera ture. We have found that benzene leaves the noncoincidence effect positive in the whole concentration range and unaltered with respect to that already observed in acetone/CCl4 mixtures at high dilution, although slightly rein forcing it. The applicability of available theories to the concentration de pendence of the non-coincidence effect in benzene is discussed.