Core-Modified Naphthalenediimides Generate Persistent Radical Anion and Cation: New Panchromatic NIR Probes

Ajayakumar, M. R.; Asthana, Deepak; Mukhopadhyay, Pritam

doi:10.1021/ol302140x

Cited by 91 publications

(76 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ligand‐to‐metal charge transfer concurs with the expected behavior for electropositive metals. This umpolung of the NDI redox chemistry, where the usually electron‐demanding NDI is changed from a reductor to an oxidant, is in line with literature reports that show the use of an NDI as cation sensor capable of undergoing one‐electron reduction …”

Section: Electron Transfer In Chromophoric Metallosalphen Compoundssupporting

confidence: 89%

A quantitative analysis of light‐driven charge transfer processes using voronoi partitioning of time dependent DFT‐derived electron densities

2017

View full text Add to dashboard Cite

An analytical method is presented that provides quantitative insight into light-driven electron density rearrangement using the output of standard time-dependent density functional theory (TD-DFT) computations on molecular compounds. Using final and initial electron densities for photochemical processes, the subtraction of summed electron density in each atomcentered Voronoi polyhedron yields the electronic charge difference, Q VECD . This subtractive method can also be used with Bader, Mulliken and Hirshfeld charges. A validation study shows Q VECD to have the most consistent performance across basis sets and good conservation of charge between electronic states. Besides vertical transitions, relaxation processes can be investigated as well. Significant electron transfer is computed for isomerization on the excited state energy surface of azobenzene. A number of linear anilinepyridinium donor-bridge-acceptor chromophores was examined using Q VECD to unravel the influence of its pi-conjugated bridge on charge separation. Finally, the usefulness of the presented method as a tool in optimizing charge transfer is shown for a homologous series of organometallic pigments. The presented work allows facile calculation of a novel, relevant quantity describing charge transfer processes at the atomic level.

show abstract

Section: Electron Transfer In Chromophoric Metallosalphen Compoundssupporting

confidence: 89%

A quantitative analysis of light‐driven charge transfer processes using voronoi partitioning of time dependent DFT‐derived electron densities

2017

View full text Add to dashboard Cite

show abstract

“…Conversion of NDI into its radical anion was achieved by chemical sensitization, for example, in the presence of cyanide anions, however, photosensitization methods to generate the radical anion of NDI are rarely reported. UV/Vis absorbance of NDI‐Ph‐Vz was observed at 297, 370, 533, and 580 nm.…”

Section: Resultsmentioning

confidence: 99%

Intersystem Crossing in Naphthalenediimide–Oxoverdazyl Dyads: Synthesis and Study of the Photophysical Properties

Hussain

Taddei²,

Bussotti³

et al. 2019

Chemistry A European J

View full text Add to dashboard Cite

Oxoverdazyl( Vz) radicalu nits were covalently linked to the naphthalenediimide (NDI) chromophore to study the effect of the radicalo nt he photophysical properties, especially the radicale nhanced intersystem crossing (REISC), which is ap romisinga pproach to develop heavyatom-free triplet photosensitizers. Rigid phenylo re thynylphenyll inkers betweent he two moieties were used, thus REISC andf ormation of doublet (D 1 ,t otal spin quantum number S = 1/2) and quartet states (Q 1 , S = 3/2) are anticipated. The photophysical properties of the dyadsw ere studied with steady-statea nd femtosecond/nanosecond transient absorption (TA) spectroscopiesa nd DFT computations. Femtosecond transienta bsorption spectras how af ast electron transfer (< 150 fs), and ISC (ca. 1.4-1.85ps) is induced by charger ecombination (CR, in toluene). Nanosecond transient absorption spectra demonstrated ab iexponential decay of the triplet state of the NDI moiety.T he fast component (lifetime:5 0ns; population ratio:8 0%)i sa ssigned to the D 1 ! D 0 decay,a nd the slow decay component (2.0 ms; 20 %) to the Q 1 !D 0 ISC. DFT computations indicated ferromagnetic interactions between the radicala nd chromophore( J = 0.07-0.13 eV). Reversible formation of the radical aniono ft he NDI moiety by photoreduction of the radical-NDI dyadsi nt he presence of sacrificial electron donor triethanolamine (TEOA) is achieved. This work is useful for design of new triplet photosensitizers based on the REISC effect.

show abstract

“…In order to shed light on the process PET in BIPy-NDIs, optimisation of the molecular geometry of the BIPy-NDI 1B was generated first with the PM6 semiempirical method and then using the density functional theory (DFT) and the nonlocal correlation B3LyP with a 6-31 + G(d,p) basis set in the gas-phase (52). Figure 5 shows the fluorophore The later prevents the PET process causing an enhancement in the fluorescence intensity.…”

Section: Sensor Response Mechanismmentioning

confidence: 99%

Photoinduced electron transfer inN,N-bis(pyridylmethyl)naphthalenediimides: study of their potential as pH chemosensors

Martinez‐Quiroz

Ochoa-Terán

Pina‐Luis

et al. 2016

Supramolecular Chemistry

View full text Add to dashboard Cite

a centro de Graduados e investigación, instituto tecnológico de tijuana, tijuana, méxico; b Departamento de investigación en polímeros y materiales, universidad de Sonora, hermosillo, méxico ABSTRACT The change in fluorescent properties of a series of N,N-bis(pyridylmethyl)naphthalenediimides (BIPy-NDIs) as function of pH were investigated. The naphthalenediimide dyes displayed OFF-ON pH sensing properties owing to photoinduced electron transfer in the pH range from 1.7 to 4.1. The fluorescence enhancement of the chemosensors studied is based on the hindering of photoinduced energy-electron transfer (PET) from pyridine ring to the naphthalene fluorophore by protonation. Moreover, using density functional theory theoretical calculations of molecular orbitals, it was verified that protonation nitrogen atom in pyridine ring inhibits the PET process. The best selective response for monitoring pH in the presence of different metal ions, was exhibited by BIPy-NDI 1B. In addition, 1B was applied for determination of pH in real samples of commercial vinegars. The results were consistent with those obtained by glass electrode method, indicating that the new probe could be a practical pH indicator in strongly acidic conditions.

show abstract

Core-Modified Naphthalenediimides Generate Persistent Radical Anion and Cation: New Panchromatic NIR Probes

Cited by 91 publications

References 30 publications

A quantitative analysis of light‐driven charge transfer processes using voronoi partitioning of time dependent DFT‐derived electron densities

A quantitative analysis of light‐driven charge transfer processes using voronoi partitioning of time dependent DFT‐derived electron densities

Intersystem Crossing in Naphthalenediimide–Oxoverdazyl Dyads: Synthesis and Study of the Photophysical Properties

Photoinduced electron transfer inN,N-bis(pyridylmethyl)naphthalenediimides: study of their potential as pH chemosensors

Contact Info

Product

Resources

About