Soret red shift for zinc tetraphenylporphine in the presence of uncharged Lewis bases

Chirogenesis in Zinc Porphyrins: Theoretical Evaluation of Electronic Transitions, Controlling Structural Factors and Axial Ligation

“…The energies of the orbitals involved in the electronic transitions in the B absorption region calculated using the aug‐cc‐pVDZ basis set are similar to those obtained using the cc‐pVTZ basis set (Table S8). It was found that axial ligation shifted the transition energies to the low energy region by about 10–19 nm (Tables 4 and S9), in agreement with the experimentally measured values of 10.4 nm reported by Kolling et al [91] . and 15.4 nm reported by Nappa et al [153] .…”

“…Axial ligation shifts the transition energies to the red region up to 26 nm as compared to ligand free flat porphyrin that is in full agreement with the previous theoretical [41,44,86,96,155] and experimental [41,44,79,96,152,156] works. Thus, Kolling et al [91] . and Nappa et al [153] .…”

“…As a result of these perturbations, the excitation energies of ligated metal porphyrins are shifted to low [41,44,79,86,96,152] or high [92] energy. For zinc porphyrins the ligation causes a red shift [91,92,153] . In addition, upon axial ligation the B electronic transitions acquire a charge transfer character [41,99] …”

A Structural Model of Nitro‐Porphyrin Dyes Based on Spectroscopy and Density Functional Theory

“…Because the phenyl groups will still shield the β nitro groups for the reasons discussed previously, this solvatochromism is likely a consequence of axial coordination of DMSO to the zinc center. There are many reports relating the magnitude of the Soret band redshift to solvent parameters such as charge, polarity, polarizability, and donor number (DN), with the latter being particularly important . In addition to the redshift, DMSO ligands have been reported to induce an increase in the Q x (0,0)/ Q x (1,0) intensity ratio, and the development of a slight shoulder on the low‐energy edge of the Soret peak, both of which are observed in the spectra for Zn(NO 2 )TPP and Zn(NO 2 ) 5 TPP.…”

Interfacially polymerized metalloporphyrin thin films for colorimetric sensing of organic vapors

“…The higher energy Q band (also known as the ␣ band) was monitored because similarly structured tetraphenylporphinatozinc has been extensively studied for its interactions with neutral donor species. It has been observed that concurrent with a red-shift of the entire spectrum, a correlated change in the relative intensities of the two Q bands occurs [29,30]. By choosing an analytical wavelength that is identical for all of the sensors, a simplified array sensor that could be constructed for rapid and high-throughput sensing is envisioned.…”