UV−Visible Absorption Spectra of [Ru(E)(E‘)(CO)2(iPr-DAB)] (E = E‘ = SnPh3or Cl; E = SnPh3or Cl, E‘ = CH3; iPr-DAB =N,N‘-Di-isopropyl-1,4-diaza-1,3-butadiene):  Combination of CASSCF/CASPT2 and TD-DFT Calculations

Abstract Effect of heteroatoms viz. BN and substituents viz. –Me (methyl), –OH (hydroxyl), –NH2 (amine), –COOH (carboxyl), and –CN (cyano) on the structural parameters, global reactivity, aromaticity, and UV-visible spectra of pyrene are studied with the help of density functional theory (DFT). Global reactivity parameters such as global hardness (η) and electrophilicity (ω) are calculated using density functional reactivity theory (DFRT). Time dependent density functional theory (TD-DFT) is explored for interpreting the UV-visible absorption spectra. Aromaticity of the pyrene rings are predicted from the nucleus independent chemical shift (NICS) values. Presence of BN unit and substituent induces reasonable impact on the studied parameters. The observed absorption spectra lie predominantly within the UV-region (both blue and red shifts are observed in presence of BN and substituent). HOMO energy and absorption spectra are affected nominally in solvent phase.

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Pyridone substituted phthalocyanines: Photophysico-chemical properties and TD-DFT calculations

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424617500730 ◽

2018 ◽

Vol 22 (01n03) ◽

pp. 25-31 ◽

Cited By ~ 2

Author(s):

Şaziye Abdurrahmanoğlu ◽

Mevlüde Canlıca ◽

John Mack ◽

Tebello Nyokong

Keyword(s):

Electronic Structure ◽

Nmr Spectroscopy ◽

Dft Calculations ◽

Chemical Properties ◽

Quantum Yields ◽

Visible Absorption ◽

H Nmr ◽

Td Dft ◽

Ft Ir ◽

Uv Visible

4-(6-methyl-3-nitro-2-oxo-1,2-dihydropyridin-4-yloxy)phthalonitrile has been used to prepare a novel Zn(II) phthalocyanines with four peripheral pyridone substituents. The compound has been characterized by UV-visible absorption, FT-IR and [Formula: see text]H-NMR spectroscopy, elemental analysis and MALDI-TOF mass spectroscopy. The fluorescence, triplet quantum and singlet oxygen quantum yields have been determined and TD-DFT calculations have been used to identify trends in the electronic structure.

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MCD spectroscopy and TD-DFT calculations of magnesium tetra-(15-crown-5-oxanthreno)-phthalocyanine

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424616500322 ◽

2016 ◽

Vol 20 (01n04) ◽

pp. 505-513 ◽

Cited By ~ 2

Author(s):

John Mack ◽

Scebi Mkhize ◽

Evgeniya A. Safonova ◽

Alexander G. Martynov ◽

Yulia G. Gorbunova ◽

...

Keyword(s):

Optical Properties ◽

Dft Calculations ◽

Electronic Structures ◽

Additional Insight ◽

Visible Absorption ◽

Model Complexes ◽

B3lyp Functional ◽

Td Dft ◽

Uv Visible ◽

Insight Into

An analysis of the MCD spectroscopy and TD-DFT calculations of magnesium tetra-(15-crown-5-oxanthreno)-phthalocyanine is reported. This study provides a reassessment of an earlier study on the nature of the bands in UV-visible absorption spectra of magnesium and zinc tetra-(15-crown-5-oxanthreno)-phthalocyanine that was based on an analysis of TD-DFT calculations for a series of model complexes with the B3LYP functional. A detailed analysis of MCD spectral data and TD-DFT calculations with the CAM-B3LYP functional for the complete Mg(II) complex provides an additional insight into the optical properties and electronic structures of tetra-(15-crown-5-oxanthreno)-phthalocyanines. Thus, the bands in the Q-band region are reassigned as being due exclusively to the Q transition of Gouterman’s 4-orbital model, since intense pseudo-[Formula: see text] terms are observed in the MCD spectrum in a spectral region that had previously been assigned as charge transfer bands.

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Naphthyridine derived colorimetric and fluorescent turn off sensors for Ni2+ in aqueous media

Scientific Reports ◽

10.1038/s41598-021-98400-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Abida Ashraf ◽

Muhammad Islam ◽

Muhammad Khalid ◽

Anthony P. Davis ◽

Muhammad Tayyeb Ahsan ◽

...

Keyword(s):

Dft Calculations ◽

Color Change ◽

Aqueous Media ◽

Field Measurements ◽

Spectral Changes ◽

Energy Gaps ◽

Td Dft ◽

Distinct Color ◽

Uv Visible ◽

Metal Charge Transfer

AbstractHighly selective and sensitive 2,7-naphthyridine based colorimetric and fluorescence “Turn Off” chemosensors (L1-L4) for detection of Ni2+ in aqueous media are reported. The receptors (L1-L4) showed a distinct color change from yellow to red by addition of Ni2+ with spectral changes in bands at 535–550 nm. The changes are reversible and pH independent. The detection limits for Ni2+ by (L1-L4) are in the range of 0.2–0.5 µM by UV–Visible data and 0.040–0.47 µM by fluorescence data, which is lower than the permissible value of Ni2+ (1.2 µM) in drinking water defined by EPA. The binding stoichiometries of L1-L4 for Ni2+ were found to be 2:1 through Job’s plot and ESI–MS analysis. Moreover the receptors can be used to quantify Ni2+ in real water samples. Formation of test strips by the dip-stick method increases the practical applicability of the Ni2+ test for “in-the-field” measurements. DFT calculations and AIM analyses supported the experimentally determined 2:1 stoichiometries of complexation. TD-DFT calculations were performed which showed slightly decreased FMO energy gaps due to ligand–metal charge transfer (LMCT).

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