Experimental and theoretical studies on bis (6-nitroquinoline) fumaric acid co-crystal

6-Nitroquinoline fumaric acid (C11H8N2O4), an organic co-crystal is grown using slow evaporation solution growth technique. The grown crystal is characterized by single crystal X-ray diffraction (SCXRD) and the title compound is crystallized in monoclinic crystal system with P2(1)/n centrosymmetric space group. The O-H center dot center dot center dot N and C-H center dot center dot center dot O hydrogen bonds influence heterodimer formation in the crystal structure. The optical absorption spectrum of the title compound shows an absorption peak at 333 nm which contributes to pi ->pi* transition. The transmission spectrum shows about 82% transparency in the visible region with lower cutoff wavelength 370 nm. The vibrational modes and assignments of functional groups are done using FTIR and Raman spectroscopic analyses. The C-O stretching is the most characteristic vibration of the carboxylic acid group and it typically appears at 1393 cm(-1). The thermal behavior of the present compound is evaluated by TG/DSC techniques and the melting point of the title crystal is 191 degrees C. The finger print plots show that H center dot center dot center dot O (41.9%) interactions are dominated interactions. These interactions are responsible for C-H center dot center dot center dot O hydrogen bonds which play vital role in the structure stabilization. The first order hyperpolarizability value is calculated using B3LYP method with the extended 6-311++ G(d,p) basis set and it is found as 4.5 times larger than that of urea. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study reveals the preparation of an organic co-crystal of 6-nitroquinoline fumaric acid and its characterization of structure and optical properties. The title compound shows 82% transparency in the visible region and exhibits high thermal stability. Furthermore, spectroscopic analysis reveals the molecular vibrations and chemical bonding properties of the compound.