Effect of non-peripheral fluorosubstitution on the structure of metal phthalocyanines and their films

In this work, we study crystal structures and thin films of tetrasubstituted metal phthalocyanines with fluorine substituents in non-peripheral positions, MPcF4-np (M = Cu(II), Co(II), Pd(II), Fe(II), Pb(II), VO). The effect of fluorosubstitution in non-peripheral positions of the phthalocyanine macmcycle on the structure of single crystals and thin films, and intermolecular interactions is elucidated and compared with that of other fluorinated phthalocyanine derivatives. MPcF4-np (M = Cu(II), Pd(II), Fe(II)) are isostructural and crystallize in the monoclinic P2(1)/c space group, while CoPcF4-np forms two polymorphs (P2(1) and P2(1)/c). Monoclinic PbPcF4-np (P2(1)/n) is packed in chains along the c axis, in which one PbPcF4-np molecule is oriented "up" and two neighboring molecules face "down". Two triclinic (P-1) phases were obtained for VOPcF4-np. For the better visualization and comparison of intermolecular contacts in different MPcF4-np, the analysis of Hirshfeld surfaces (HS) was carried out. All investigated MPcF4-np derivatives form thin films with a strong preferred orientation. The effect of the positions of F-substituents on the electronic absorption spectra of MPcF4 solutions and thin films is also discussed.