Crystal and Electronic Structure of 2,9-Dichlorodithioketoquinacridone - Polymorph of Dimethylacetamide-Solvated Crystals -

摘要

2,9-Dichlorodithioketoquinacridone (DTQ-Cl: Fig.1(a)) is a thionated derivative of industrially important 2,9-dichloroquinacridone used as colorants in painting and imaging industries. Crystallographic and electronic characterization has been carried out on dimethylacetamide-solvated single crystals: DTQ-Cl/(DMA)_2. There are two crystal Modifications Ⅰ and Ⅱ which crystallize in the space group of P2_1/c and P-1, respectively. In both crystals, two DMA molecules are hydrogen-bonded to one DTQ-Cl molecule. A larger bathochromic is observed on going from solution to the solid state in Modification Ⅱ than in Modification Ⅰ (730 and 520 cm~(-1)). This is presumably due to larger excitonic interactions between transition dipoles in modification Ⅱ than in modification Ⅰ.