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Gas-Phase Electronic Structure of Phthalocyanine Ions: A Study of Symmetry and Solvation Effects.

ABSTRACT: Research into and applications of phthalocyanines (Pc) are mostly connected to their intriguing electronic properties. Here, messenger-type UV-vis spectroscopy of two metal-free ions from the phthalocyanine family, cationic H₂Pc⁺ and H₂PcD⁺, along with their hydrates is performed. They show that the electronic properties of both ions can be traced to those in the conjugate base, Pc^2-, however, they are affected by state splitting due to the reduced symmetry; in the H₂Pc⁺ radical cation, a new band appears due to excitations into the singly-occupied molecular orbital. Quantum chemical spectra modeling reproduces all important features of the measured spectra and provides insight into the nature of electronic transitions. Hydration of the ions has only a mild effect on the electronic spectra, showing the stability of the electronic structure with respect to solvation effects.

SUBMITTER: Bergmeister S

PROVIDER: S-EPMC10966524 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Gas-Phase Electronic Structure of Phthalocyanine Ions: A Study of Symmetry and Solvation Effects.

Bergmeister Stefan S Ganner Lisa L Ončák Milan M Gruber Elisabeth E

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20240115 12

Research into and applications of phthalocyanines (Pc) are mostly connected to their intriguing electronic properties. Here, messenger-type UV-vis spectroscopy of two metal-free ions from the phthalocyanine family, cationic H2Pc+ and H2PcD+, along with their hydrates is performed. They show that the electronic properties of both ions can be traced to those in the conjugate base, Pc2-, however, they are affected by state splitting due to the ...[more]

PMID: 38225692

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