The belief that the position of the absorption maximum is directly proportional to the length of the conjugated system implies that lycopene and β-carotene, both having 11 conjugated  bonds in which 22 electrons shuffle (Fig. ) ought to have a much longer  max than say, 1 with only four conjugated  bonds (Fig. ). Brushing the effects of non-bonding orbitals in 1 aside, the  max of lycopene/β-carotene seems to be close to that of 1, as all exhibit orangish-red colour. This discrepancy stems from the fact that for a 1-dimensional observable 'particle in a box', its invariant symmetrical potential V(x) with respect to space inversion is as follows: