Abstract
(1,4,7,10,13,16-Hexaoxacyclooctadecane-κ6O)potassium pentaiodide, [K(C12H24O6)]I5, obtained by slow evaporation of an ethanol solution of KI, 18-crown-6 and I2, contains [K(18-crown-6)]+ cations (Ci symmetry) and I5− anions (C2 symmetry), which are arranged in alternating layers parallel to (001). In contrast to the well known tendency of I5− ions to form chains and nets, the I5− units in the title compound are isolated.