Molpro restart files (ASCII compressed) for the XSURF program of the potential energy surfaces for HCCNCS AND DCCNCS. The expansion point of these surfaces is the 2nd order transition state of the linear structure. Vibrational structure calculations based on these surfaces are reported in "A combined computational and experimental study on the vibrational structure of ethynyl isothiocyanate, HCCNCS, a molecule with a Champagne bottle potential" (https://doi.org/10.1016/j.jms.2022.111626).