Sulfur-substituted perylene diimides: efficient tuning of LUMO levels and visible-light absorption via sulfur redox.

A series of sulfide and sulfone substituted perylene diimides (PDIs) with different LUMO levels covering a range of 0.72 eV were synthesized through simple sulfur redox chemistry. The LUMO level of phenylsulfone substituted PDI reached a record-breaking -4.75 eV. In addition, the maximum emission ranged from 540 to 692 nm.