Sn 2 SbS 2 I 3 single crystals were grown by chemical vapour transport using iodine as the transport agent. An evacuated and sealed quartz glass ampoule containing the starting materials and the additional halogen (5 mg/cm 3 ) was placed in a two-zone furnace with a temperature gradient from 450 °C to 350 °C. After a growth time of 240 hours, needle-like crystals with a length of up to 10 mm and a diameter of 1-2 mm were obtained (Figure ).