Abstract: | The title compound, K2[VF5(H2O)], was synthesized from potassium antimony tartrate, piperazine, V2O5 and HF under hydrothermal conditions. It is isostructural with K2[FeF5(H2O)] and contains polymeric anion chains held together by strong O—H⋯F bonds. Each V atom is coordinated to five terminal F atoms and the O atom of one water molecule. Pairs of O—H⋯F bonds are formed by two cis‐related F atoms. Twofold axes run along the O—V—F axis of the V‐centred otahedra. |