Thiocyanate shares its negative charge approximately equally between sulfur and nitrogen. Thiocyanate can bind metals at either sulfur or nitrogen — it is an ambidentate ligand. Other factors, e.g. kinetics and solubility, sometimes influence the observed isomer. For example, [Co(NH)(NCS)] is the thermodynamic isomer, but [Co(NH)(SCN)] forms as the kinetic product of the reaction of thiocyanate salts with [Co(NH)(HO)].
Some complexes of SCN feature both but only thiocyanate and isothiocyanate ligands.  Examples are found for heavy metals in the middle of the d-period: Ir(III), and Re(IV).