A novel AB3-type trimeric zinc(II)-phthalocyanine as an electrochromic and optical limiting material

Recent advances in the practical applications of metallophthalocyanines (MPcs) in different technological fields have stimulated us to design and synthesize a new asymmetric AB3-type trimeric zinc(ii)-phthalocyanine (1). This bulky and high molecular weight compound was characterized by elemental analysis, 1H, 13C DEPT, and 1H-1H NOESY NMR, HR MALDI-TOF mass spectrometry, UV-vis, and FT-IR (ATR) techniques. In-depth electrochemical studies show that 1 displays quasi-reversible three one-electron reductions and two one- or two-electron oxidation processes, rather than any redox processes including the transfer of three-electrons in one-step. Besides this, in situ spectroelectrochemical measurements suggest the good application potential of 1 as an electrochromic material in display technologies. A study of the nonlinear optical properties (NLOs) of 1 reveals that the poly(methylmethacrylate) (PMMA) composite film displays a much larger nonlinear absorption coefficient and a lower saturable absorption threshold for optical limiting when compared to the same Pc molecules in solution. Ultrafast transient absorption measurements reveal the intersystem crossing mechanism. Density functional theory (DFT) was used for the geometry optimizations and time dependent-DFT (TD-DFT) for HOMO/LUMO energies and electronic transitions for 1.

Synthesis, characterization and structural computational investigation of novel Zn(II) phthalocyanines containing peripheral anthracene moieties

New zinc(II) phthalocyanines (ZnPc-I and ZnPc-II) containing four peripheral anthracene pendant groups were synthesized by cyclotetramerization of (E)-4-(3-(4-((anthracen-9-yl-methylene)amino)phenoxy)propoxy)phthalonitrile and 4-(3-(4-((anthracen-9-ylmethyl)amino)phenoxy)propoxy)phthalonitrile. All compounds were characterized using a combination of analytical and spectroscopic techniques such 1H, [Formula: see text]C NMR, FT-IR, UV-vis and MS spectral data. The molecular geometry and gauge including atomic orbital (GIAO) 1H and [Formula: see text]C chemical shift values of the compounds in the ground state have also been calculated using B3LYP with the 6–31G([Formula: see text] basis set. The chemical shift of the optimized molecular structure is compared with the experimental chemical shift values.