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Magnetic circular dichroism (MCD) and UV-Vis-NIR spectroscopy were used to investigate the spectroscopic signatures of the triplet-multiplet and other transitions observed in the simplest [Formula: see text] (Pc^tBuCu and Pc^(SO3Na)4Cu) and [Formula: see text] (Pc^tBuV=O and TPz^(OAr)8V=O) phthalocyanine systems. Density Functional Theory (DFT) and time-dependent DFT (TDDFT) calculations allowed accurate correlation between the experimental and theoretical data. In particular, similarities between vibronic profiles in Q-band and triplet-multiplet band regions as well as the presence of MCD [Formula: see text]-terms associated with the 0-0 transitions support the relationship between the Q- and triplet-multiplet transitions. 

The electronic structures, charge-transfer, and triplet–multiplet transitions in cobalt(i), cobalt(ii), and cobalt(iii) phthalocyanines were investigated in detail by UV-vis-NIR, MCD, DFT, and TDDFT methods. 

The molecular structure of the unsubstituted iron(III) phthalocyanine [Formula: see text]-oxo(1) dimer ((PcFe)₂O) was determined by single crystal X-ray diffraction. In agreement with the earlier speculations, the dimer has a bent (Fe-O-Fe angle is 152.4[Formula: see text]) structure. The interplay between the [Formula: see text]-[Formula: see text] interactions and steric hindrances caused by the isoindole units led to the observed staggering angle of [Formula: see text]24[Formula: see text] between two phthalocyanine ligands. The high-spin iron(III) centers are located significantly above the phthalocyanine N4 planes (0.57–0.58 Å). Several DFT exchange-correlation functionals were used to calculate the absolute value and sign of the Mössbauer quadrupole splitting and antiferromagnetic coupling constant for X-ray determined geometry of (PcFe)₂O. It was demonstrated that the hybrid functionals provide the correct sign of the electric field gradient and the magnitude of the antiferromagnetic coupling constant compared to the pure functionals.