X-Ray, Hirshfeld surface analysis, spectroscopic and DFT studies of polycyclic aromatic hydrocarbons: Fluoranthene and acenaphthene

Abstract

The X-ray structure, theoretical calculation, Hirshfeld surfaces analysis, IR and Raman spectra of fluoranthene and acenaphthene were reported. Acenaphthene crystallizes in the orthorhombic crystal system and space group P21ma, with crystal parameters a = 7.2053(9) Å, b = 13.9800(15) Å, c = = 8.2638 (8) Å, Z = 4 and V = 832.41(16) Å3. In turn, the grown crystals of fluoranthene are in the monoclinic system with space group P21/n. The unit cell parameters are a = 18.3490(2) Å, b = 6.2273(5) Å, c = 19.8610(2) Å, ß = = 109.787(13)°, Z = 8 and the unit cell volume is 2135.50(4) Å3. Theoretical calculations of isolated molecules of the title compounds were performed using DFT at the B3LYP level. The intermolecular interactions in the crystal structure, for both the title polycyclic aromatic hydrocarbons were analyzed using the Hirshfeld surfaces computational method.