کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
177948 459008 2006 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Polymorph of dimethylacetamide-solvated crystals of 2,9-dichlorodithioketoquinacridone and their hydrogen bonding effect
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Polymorph of dimethylacetamide-solvated crystals of 2,9-dichlorodithioketoquinacridone and their hydrogen bonding effect
چکیده انگلیسی

2,9-Dichlorodithioketoquinacridone (DTQ-Cl) is a thionated derivative of industrially important 2,9-dichloroquinacridone used as colorants in painting and imaging industries. Crystallographic and electronic characterizations have been carried out on single crystals of DTQ-Cl recrystallized from solution in dimethylacetamide (DMA). Two kinds of DMA-solvated single crystals were isolated in the form of DTQ-Cl/(DMA)2: modifications I and II. In both crystals, two DMA molecules are hydrogen-bonded to one DTQ-Cl molecule. Modifications I and II crystallize in different space groups: P21/c   and P1¯, respectively. The DTQ-Cl molecules are arranged in a fashion “hunter's fence” in modification I; whereas all DTQ-Cl molecules are nearly on the molecular plane and stacked in a layered structure in modification II. MO calculations based on the X-ray coordinates revealed that the absorption bands for both DTQ-Cl and DTQ-Cl/(DMA)2 are expected to appear at longer wavelengths in modification I than in modification II. However, the reverse is the case in experiment. This can be attributed to the difference in excitonic interactions along the stacking axis in modifications I and II.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Dyes and Pigments - Volume 69, Issues 1–2, 2006, Pages 54–61
نویسندگان
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