MCD spectroscopy and TD-DFT calculations of low-symmetry acenaphthoporphyrins with dual fluorescence

Magnetic circular dichroism (MCD) spectroscopy and TD-DFT calculations are used to analyze the electronic structure and optical properties of low-symmetry acenaphthoporphyrins with AAAB, ABAB and AABB structures. Evidence for dual fluorescence caused by tautomerism has been identified in the emission spectra of the AAAB and ABAB compounds. The sign sequences observed for the Q and B bands in the MCD spectra have been used to validate the results of the TD-DFT calculations. An anomalous +/- sign sequence is observed in the B band region with ascending energy similar to that reported previously for metal tetraphenyltetraacenaphthoporphyrin complexes.

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MCD spectroscopy and TD-DFT calculations of a naphthalene-ring-bridged coplanar binuclear phthalocyanine dimer

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424613500259 ◽

2013 ◽

Vol 17 (06n07) ◽

pp. 489-500 ◽

Cited By ~ 9

Author(s):

John Mack ◽

Xu Liang ◽

Tatiana V. Dubinina ◽

Larisa G. Tomilova ◽

Tebello Nyokong ◽

...

Keyword(s):

Experimental Data ◽

Optical Properties ◽

Electronic Structure ◽

Dft Calculations ◽

Singlet Oxygen ◽

Magnetic Circular Dichroism ◽

Basis Sets ◽

Naphthalene Ring ◽

B3lyp Functional ◽

Td Dft

Magnetic circular dichroism (MCD) spectroscopy and TD-DFT calculations are used to analyze the electronic structure and optical properties of an alkyl-substituted naphthalene-ring-bridged coplanar binuclear phthalocyanine dimer. An analysis of the MCD spectrum of the naphthalene-ring-bridged dimer relative to those of benzene-bridged compounds reported previously, demonstrates that there is a significantly weaker interaction between the two phthalocyanine rings. TD-DFT results obtained using the B3LYP functional with 6–31G basis sets were found to be problematic. Closer agreement with the experimental data is obtained when the CAM-B3LYP functional is used instead. The naphthalene-ring-bridged compound is found to be unsuitable for use as a photosensitizer for the formation of singlet oxygen, because the ΦT values are negligible.

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Trends in the TD-DFT calculations of porphyrin and phthalocyanine analogs

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461450045x ◽

2014 ◽

Vol 18 (08n09) ◽

pp. 630-641 ◽

Cited By ~ 21

Author(s):

John Mack ◽

Justin Stone ◽

Tebello Nyokong

Keyword(s):

Dft Calculations ◽

Excited States ◽

Magnetic Circular Dichroism ◽

Exchange Potential ◽

Configurational Interaction ◽

Exchange Correlation ◽

Hartree Fock ◽

Band Region ◽

Td Dft ◽

Range Correction

In 2005, Kobayashi and coworkers reported trends in the TD-DFT spectra of 17 Zn ( II ) porphyrinoids [J. Am. Chem. Soc. 2005; 127: 17697] that were analyzed using Michl's perimeter model as part of a study of the anomalous magnetic circular dichroism (MCD) spectroscopy of zinc tetraphenyltetraacenaphthoporphyrin. In recent years, it has become increasingly clear that TD-DFT calculations with the commonly used hybrid B3LYP exchange-correlation functional of the Gaussian software package are problematic in the B -band region of porphyrinoid spectra, since the degree of configurational interaction between the B and higher energy ππ* state appears to be significantly overestimated. The CAM-B3LYP functional is now often preferred for analyzing the optical properties of porphyrinoids, since it includes a long-range correction of the exchange potential, which incorporates an increasing fraction of Hartree–Fock (HF) exchange as the interelectronic separation increases, making it better suited for studying compounds where there is significant charge transfer in the electronic excited states. The trends in the TD-DFT calculations are reexamined with a wider range porphyrinoid compounds including several with pyrazino moieties and are found to provide a closer agreement with the experimental in the B -band region for complexes such as zinc tetraphenylporphyrin and phthalocyanine.

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TlInGe2S6, A Prospective Nonlinear Optical Material: First-Principles DFT Calculations of the Electronic Structure and Optical Properties

Journal of Electronic Materials ◽

10.1007/s11664-018-6449-5 ◽

2018 ◽

Vol 47 (9) ◽

pp. 5525-5536 ◽

Cited By ~ 6

Author(s):

Tuan V. Vu ◽

A. A. Lavrentyev ◽

B. V. Gabrelian ◽

O. V. Parasyuk ◽

O. Y. Khyzhun

Keyword(s):

Optical Properties ◽

Electronic Structure ◽

Dft Calculations ◽

First Principles ◽

Nonlinear Optical ◽

Optical Material ◽

Nonlinear Optical Material

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Electronic structure and optical properties of Cs2HgI4: Experimental study and band-structure DFT calculations

Optical Materials ◽

10.1016/j.optmat.2015.01.026 ◽

2015 ◽

Vol 42 ◽

pp. 351-360 ◽

Cited By ~ 20

Author(s):

A.A. Lavrentyev ◽

B.V. Gabrelian ◽

V.T. Vu ◽

P.N. Shkumat ◽

G.L. Myronchuk ◽

...

Keyword(s):

Experimental Study ◽

Optical Properties ◽

Electronic Structure ◽

Band Structure ◽

Dft Calculations

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Optical and nonlinear optical properties of Ln(Tp)2, where Ln = La,…,Lu and Tp = tris(pyrazolyl)borate: a DFT+TD-DFT study

New Journal of Chemistry ◽

10.1039/c9nj03232k ◽

2019 ◽

Vol 43 (36) ◽

pp. 14377-14389 ◽

Cited By ~ 1

Author(s):

Douniazed Hannachi ◽

Mohamed Fahim Haroun ◽

Ahlem Khireddine ◽

Henry Chermette

Keyword(s):

Optical Properties ◽

Thermodynamic Properties ◽

Dft Calculations ◽

Rare Earths ◽

Magnetic Moment ◽

Nonlinear Optical ◽

Dft Study ◽

Dynamic Polarizability ◽

Td Dft ◽

Borate Complexes

DFT calculations of electronic, structural, thermodynamic properties, magnetic moment, static and dynamic polarizability and hyperpolarizability of Ln(Tp)2 (Ln = rare earths, Tp = ring-unsubstituted tris(pyrazolyl)borate) complexes.

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