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

2014 ◽  
Vol 18 (08n09) ◽  
pp. 630-641 ◽  
Author(s):  
John Mack ◽  
Justin Stone ◽  
Tebello Nyokong

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.

2013 ◽  
Vol 17 (10) ◽  
pp. 996-1007 ◽  
Author(s):  
John Mack ◽  
Jun Nakamura ◽  
Tetsuo Okujima ◽  
Hiroko Yamada ◽  
Hidemitsu Uno ◽  
...  

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.


2014 ◽  
Vol 18 (06) ◽  
pp. 475-492 ◽  
Author(s):  
Neha Agnihotri ◽  
Ronald P. Steer

The molecular orbital energies and symmetries, electronic state energies and symmetries, and orbital compositions and oscillator strengths for one-photon radiative transitions up to an energy of 4 eV have been calculated by DFT and TD-DFT methods for 15 d0 and d10 metalloporphyrins. Data for both singlet and triplet excited states are reported and used to identify potential candidates for use as photon upconverters by homomolecular triplet–triplet annihilation.


2014 ◽  
Vol 53 (13) ◽  
pp. 6624-6633 ◽  
Author(s):  
Jamal Moussa ◽  
Lise-Marie Chamoreau ◽  
Alessandra Degli Esposti ◽  
Maria Pia Gullo ◽  
Andrea Barbieri ◽  
...  

2014 ◽  
Vol 43 (47) ◽  
pp. 17703-17711 ◽  
Author(s):  
Sergey Ketkov ◽  
Nikolai Isachenkov ◽  
Elena Rychagova ◽  
Wen-Bih Tzeng

The influence of the (η6-arene)2M (M = Cr, V, Cr+) composition on parameters of intravalency and Rydberg transitions is explained on the basis of time-dependent DFT.


2013 ◽  
Vol 17 (06n07) ◽  
pp. 489-500 ◽  
Author(s):  
John Mack ◽  
Xu Liang ◽  
Tatiana V. Dubinina ◽  
Larisa G. Tomilova ◽  
Tebello Nyokong ◽  
...  

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.


2014 ◽  
Vol 5 (11) ◽  
pp. 1806-1811 ◽  
Author(s):  
Fabrizio Santoro ◽  
Roberto Improta ◽  
Tobias Fahleson ◽  
Joanna Kauczor ◽  
Patrick Norman ◽  
...  

2020 ◽  
Vol 22 (28) ◽  
pp. 16387-16399 ◽  
Author(s):  
Tom Cardeynaels ◽  
Simon Paredis ◽  
Jasper Deckers ◽  
Sonny Brebels ◽  
Dirk Vanderzande ◽  
...  

In view of designing organic dyes for TADF, TD-DFT calculations are performed on 10 prototypical donor-acceptor compounds and are benchmarked against riCC2 calculations, demonstrating that modified range-separated hybrids perform best.


2014 ◽  
Vol 43 (47) ◽  
pp. 17820-17827 ◽  
Author(s):  
Elena N. Golubeva ◽  
Ekaterina M. Zubanova ◽  
Michail Ya. Melnikov ◽  
Fedor E. Gostev ◽  
Ivan V. Shelaev ◽  
...  

Photoinduced processes of tetrahexylammonium tetrachlorocuprate [(C6H13)4N]2CuIICl4 in chloro-organic solvents were investigated by steady state photolysis and femtosecond transient absorption spectroscopy, as well as TD-DFT calculations of excited terms.


2014 ◽  
Vol 33 (13) ◽  
pp. 3251-3264 ◽  
Author(s):  
Gregg S. Kottas ◽  
Thierry Brotin ◽  
Peter F. H. Schwab ◽  
Kamal Gala ◽  
Zdeněk Havlas ◽  
...  

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