OCN- The isoelectronic cyanate ion, OCN- (Figure 3-4), has the same possibilities, but
the larger electronegativity of 0 makes structure B more important than in thiocyanate. The
protonated form contains 97% HNCO and 3% HOCN, consistent with structure A and a small
contribution from B. The bond lengths in OCN- and HNCO in Table 3-2 are consistent with
this picture, but do not agree perfectly.