Relationship between Two-Photon Absorption and the π-Conjugation Pathway in Porphyrin Arrays through Dihedral Angle Control

Ahn, Tae Kyu; Kim, Kil Suk; Kim, Deok Yun; Noh, Su Bum; Aratani, Naoki; Ikeda, Chikako; Osuka, Atsuhiro; Kim, Dongho

doi:10.1021/ja056773a

Cited by 210 publications

(137 citation statements)

References 17 publications

Supporting

Mentioning

126

Contrasting

Unclassified

Order By: Relevance

“…The enhanced 2PA is attributed to the completely flat dimerization of the adjacent porphyrins. Hexaphyrins bearing σ (2) values of around 9900 GM at a longer wavelength of 1200 nm, due to the expanded aromatic structure, have also been reported by the same group [28,29] (Scheme 4, bottom). The molecules, without any reversible property, such as photochromism, which gives 0↔1 information transformation, may only provide read only memory (ROM) through a photobleaching process by two-photon irradiation, even though they exhibit high 2PA efficiency.…”

Section: Scheme 2 Dendritic Two-photon Absorbing Moleculesmentioning

confidence: 85%

Two-Photon Absorbing Molecules as Potential Materials for 3D Optical Memory

Ogawa

2014

Applied Sciences

View full text Add to dashboard Cite

Abstract:In this review, recent advances in two-photon absorbing photochromic molecules, as potential materials for 3D optical memory, are presented. The investigations introduced in this review indicate that 3D data storage processing at the molecular level is possible. As 3D memory using two-photon absorption allows advantages over existing systems, the use of two-photon absorbing photochromic molecules is preferable. Although there are some photochromic molecules with good properties for memory, in most cases, the two-photon absorption efficiency is not high. Photochromic molecules with high two-photon absorption efficiency are desired. Recently, molecules having much larger two-photon absorption cross sections over 10,000 GM (GM= 10 ) have been discovered and are expected to open the way to realize two-photon absorption 3D data storage.

show abstract

Section: Scheme 2 Dendritic Two-photon Absorbing Moleculesmentioning

confidence: 85%

Two-Photon Absorbing Molecules as Potential Materials for 3D Optical Memory

Ogawa

2014

Applied Sciences

View full text Add to dashboard Cite

show abstract

“…Additionally, referring to the previous reports, we can obtain information on delocalized π-conjugation pathway, excitonic coupling and molecular planarity from two-photon absorption (TPA) measurement. [14][15][16] In order to check the enhanced excitonic interactions accompanied by structural rigidity and delocalized π-conjugation, we have performed TPA measurement by an open aperture femtosecond Z-scan method with excitation at 800 nm, as shown in Figure 5. As indicated in Table 1, the TPA cross-section σ (2) values of ZNH remain intact with elongated molecular length, whereas that of ZNHG increases dramatically being consistent with the elongated π-conjugation length arising from reduced dihedral angle between porphyrin moieties.…”

Section: Resultsmentioning

confidence: 99%

“…By reducing the conformational heterogeneity, the formation of helical arrays has also allowed the enhanced nonlinear optical response probed by femtosecond Z-scan technique. 14 …”

Section: Introductionmentioning

confidence: 99%

Zn(II)porphyrin Helical Arrays: A Strategy to Overcome Conformational Heterogeneity by Host-Guest Chemistry

Yoon

Easwaramoorthi

Kim

2008

Bulletin of the Korean Chemical Society

View full text Add to dashboard Cite

Conformational heterogeneity of directly linked multiporphyrin arrays with larger molecular length retards their utilities in practical applications such as two-photon absorption and molecular photonic wire. In this regard, here we adopted a way to overcome the conformational heterogeneity through hydrogen bonding by selective binding of meso aryl substituents of porphyrins (host) with urea (guest) to form helical structure. Using steady-state and time-resolved spectroscopy, we observed the enhanced fluorescence quantum yield bỹ 1.8 to 2.4 times, enhanced anisotropy values and the disappearance of fast fluorescence decay component in the host-guest helical forms. In addition, the enhanced nonlinear optical responses of helical arrays infer the extended inter-porphyrin electronic coupling due to a significant change in dihedral angle between the neighboring porphyrin moieties. The current host-guest strategy will provide a guideline to improve the structural homogeneity of the photonic wire.

show abstract

“…D-π-A dipoles, D-π-A-π-D quadrupoles and more complex (D-π-) 3 A octupoles (where D and A denote respectively electron donors and acceptors and 'π' is a π-conjugated bridge), however materials based on porphyrins, 13,14 multi-annulenes, 15 polymers and nano-aggregates 16 have also been extensively studied. Arylamines are the most frequently used structural motif playing the role of an electron donor, whereas many different electron acceptors have been tested.…”

Section: Introductionmentioning

confidence: 99%

An internal charge transfer-dependent solvent effect in V-shaped azacyanines

et al. 2015

View full text Add to dashboard Cite

a New V-shaped non-centrosymmetric dyes, possessing a strongly electron-deficient azacyanine core, have been synthesized based on a straightforward two-step approach. The key step in this synthesis involves palladium-catalysed cross-coupling of dibromo-N,N'-methylene-2,2'-azapyridinocyanines with arylacetylenes. The resulting strongly polarized π-expanded heterocycles exhibit green to orange fluorescence and they strongly respond to changes in solvent polarity. We demonstrate that differently electron-donating peripheral groups have a significant influence on the internal charge transfer, hence on the solvent effect and fluorescence quantum yield. TD-DFT calculations confirm that, in contrast to the previously studied bis(styryl)azacyanines, the proximity of S 1 and T 2 states calculated for compounds bearing two 4-N,N-dimethylaminophenylethynyl moieties establishes good conditions for efficient intersystem crossing and is responsible for its low fluorescence quantum yield. Non-linear properties have also been determined for new azacyanines and the results show that depending on peripheral groups, the synthesized dyes exhibit small to large two-photon absorption cross sections reaching 4000 GM.

show abstract

Relationship between Two-Photon Absorption and the π-Conjugation Pathway in Porphyrin Arrays through Dihedral Angle Control

Cited by 210 publications

References 17 publications

Two-Photon Absorbing Molecules as Potential Materials for 3D Optical Memory

Two-Photon Absorbing Molecules as Potential Materials for 3D Optical Memory

Zn(II)porphyrin Helical Arrays: A Strategy to Overcome Conformational Heterogeneity by Host-Guest Chemistry

An internal charge transfer-dependent solvent effect in V-shaped azacyanines

Contact Info

Product

Resources

About