Jülich researchers have succeeded in controlling the growth of organic molecules using a special trick. Molecules that repel each other play a key role in this process: due to their opposing forces, they always keep a certain distance from their neighbours. Therefore, they mix easily with a second, mutually attracting type of molecule that enters the spaces in-between and acts as a sort of “glue”. Tailored surface structures can thus be put together like pieces in a puzzle – in a seemingly self-solving manner. Applications in the field of organic electronics in particular could stand to benefit from this method.