Solid-State Optical Properties and Crystal Structures of 1,4-Dipropoxy-9,10-anthraquinone Polymorphs

Abstract

Recrystallization of 1,4-dipropoxy-9,10-anthraquinone from hexane solution afforded two polymorphs: red prisms and yellow needles. X-ray crystallographic analyses revealed that the molecular arrangement was an anti-parallel orientation for red solids and a slipped-parallel orientation for yellow solids. The difference in solid-state color was analyzed by TD-DFT calculations of their multimers.