A5101626429- Nonlinear Optical Materials Studies
- Nonlinear Optical Materials Research
- Luminescence and Fluorescent Materials
- Porphyrin and Phthalocyanine Chemistry
- Photochromic and Fluorescence Chemistry
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Synthesis and Properties of Aromatic Compounds
- Photochemistry and Electron Transfer Studies
- Luminescence Properties of Advanced Materials
- Molecular Sensors and Ion Detection
- Organic Electronics and Photovoltaics
- Perovskite Materials and Applications
- Molecular spectroscopy and chirality
- Laser-Matter Interactions and Applications
- Electron Spin Resonance Studies
- Photoreceptor and optogenetics research
- Spectroscopy and Quantum Chemical Studies
- Organic Light-Emitting Diodes Research
- Magnetism in coordination complexes
- Organic Chemistry Cycloaddition Reactions
- Advanced Chemical Physics Studies
- Graphene research and applications
- Organic and Molecular Conductors Research
- Orbital Angular Momentum in Optics
National Institute of Advanced Industrial Science and Technology
2015-2024
Kwansei Gakuin University
2014-2024
Nanomaterials Research (United States)
2024
Ikeda Municipal Hospital
2015-2020
École Normale Supérieure de Lyon
2007-2014
Centre National de la Recherche Scientifique
2007-2014
Université Claude Bernard Lyon 1
2013-2014
Osaka University
1990-2013
Shimizu (Japan)
2013
Laboratoire de Chimie
2007-2013
The characteristics of the edge state, which is a peculiar magnetic state in zigzag-edged graphene nanoribbons (ZGNRs) that originates from electron-electron correlation an edge-localized π-state, are investigated by preparing and characterizing quarteranthene molecules. molecular geometry was determined X-ray analysis consistent with zigzag-edge-localized structure unpaired electrons. localized electrons responsible for (room-temperature ferromagnetic correlation), optical (the lowest-lying...
The dependence of the second hyperpolarizability (gamma) on diradical character (y) for singlet systems is investigated using a model compound, p-quinodimethane (PQM) molecule with different both-end carbon-carbon (C-C) bond lengths, by several ab initio molecular orbital and density functional theory methods. based UHF calculations indicates that at equilibrium geometry PQM in ground state primarily exhibits quinoid structure, whereas increases when increasing C-C lengths. At highest level...
Ones and twos: The two-photon absorption cross sections (σ(2)) of singlet diradical hydrocarbons with phenalenyl peripheral groups (see scheme) are larger than those closed-shell aromatic by an order magnitude or more comparable to π-conjugated compounds strong electron donor acceptor substituents. A significant increase in section was also observed the resonance-enhanced region. Supporting information for this article is available on WWW under...
Although most third-order nonlinear optical (NLO) materials are closed-shell singlet systems, this Letter theoretically shows that the NLO properties drastically enhanced in symmetric open-shell diradical systems with intermediate character and further reveals enhancement is associated ferromagnetic antiferromagnetic interactions. This new paradigm opens up a promising area for designing materials.
Understanding the electronic structure of singlet diradical state tackles fundamentals chemical bond itself. The character is a key factor, which determines reactivity, reaction products, as well chemical/physical (electronic, optical and magnetic) properties, although this quantity defined in purely theoretical manner. In Letter, on basis valence configuration interaction scheme, we present an explicit connection between measured quantities obtained from one- two-photon absorption spectra...
Dipolar and symmetrical heptamethine dyes featuring strong linear absorption in the near-infrared spectral range (700−900 nm) were prepared at a gram scale. X-ray crystallographic structure of dipolar chromophore is described revealing remarkable planarity polyenic chain due to central ring molecule. These chromophores present promising nonlinear properties telecommunication wavelengths (1400−1600 nm): (i) significant two-photon cross-sections measured using femtosecond Z-scan method, (ii)...
Aza boron-dipyrromethene dyes functionalized by extended donor-π-conjugated moieties present high potentialities for nonlinear applications in the telecommunication spectral range (1300–1500 nm). Their significant two-photon absorption cross-sections (σ2 > 600 GM) over this entire range, combined with their stability and solubility, allow transmission experiments. Detailed facts of importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but...
The two-photon absorption (TPA) of a bis(acridine) dimer (8) having singlet diradical character in its ground state was found to be enhanced by more than 2 orders magnitude as compared closed-shell counterpart (12), which has the same structural backbone and atom composition. dimer, tetracation species consisting two connected acridinium cation moieties with high coplanarity, obtained during our attempts synthesize triplet carbenes double oxidation an allenic precursor (3b). High conjugation...
The first synthesis of an all-benzene carbon nanocage 1, which represents a junction unit branched nanotubes, has been achieved. A stepwise assembly six L-shaped units [cis-di(p-bromophenyl)cyclohexane derivative] and two three-way (1,3,5-triborylbenzene) by cross-coupling homocoupling provided the unstrained cyclic precursor. Acid-mediated aromatization cyclohexane moieties in precursor resulted formation 1. Photophysical measurements DFT studies revealed unique properties such as D3...
Switching on an external electric field (F) along the electron correlation direction produces a giant enhancement of second hyperpolarizability γ in polyaromatic diradicaloid having intermediate diradical character. This has been evidenced by carrying out spin-unrestricted density functional theory calculations with LC-UBLYP long-range corrected exchange-correlation for s-indaceno[1,2,3-cd;5,6,7-c′d′]diphenalene (IDPL) compound comparison to closed-shell analogue similar size composed two...
The synthesis of boron difluoride complexes a series curcuminoid derivatives containing various donor end groups is described. Time-dependent (TD)-DFT calculations confirm the charge-transfer character second lowest-energy transition band and ascribe lowest energy to "cyanine-like" transition. Photophysical studies reveal that tuning strength allows covering broad spectral range, from visible NIR region, UV-visible absorption fluorescence spectra. Two-photon-excited Z-scan techniques prove...
Binary crystalline solids <italic>via</italic> solution casting under rapid drying conditions were found to show efficient triplet–triplet annihilation upconversion by suppressing the segregation of components.
Kinetics of triplet–triplet annihilation photon upconversion is organized from the basics for non-experts and experts. From self-consistent analyses tangled photophysical events, many important useful relations are derived summarized.
Two-photon absorption (2PA) properties of self-assembled porphyrins were investigated. The butadiyne-linked porphyrin array exhibited a 20 times larger 2PA cross section than the meso-meso-linked due to expansion pi-conjugation. Higher-order nonlinear was also observed in former porphyrin.
Within the spin-unrestricted density functional theory (DFT) long-range correction (LC) scheme combined with Becke-Lee-Yang-Parr exchange-correlation functional, referred to as LC-UBLYP method, has been applied calculation of second hyperpolarizability (gamma) open-shell singlet diradical systems increasing complexity and demonstrated good performance: (i) for simplest H(2) dissociation model, gamma values calculated by method significantly overshoot full configuration interaction result but...
Spectroscopic properties, two-photon absorption (TPA) and excited state (ESA), of two organic cyanine dyes a ruthenium based organometallic are compared in order to rationalize their similar ns-optical power limiting (OPL) efficiency the telecommunication wavelength range. The TPA contribution ns-OPL behavior is higher for both cyanines, while main process TPA-induced ESA case system, which induces broadening NIR-ESA band resulting strong spectral overlap between spectra.
Herein, triplet-triplet annihilation upconversion (TTA-UC) from near-infrared (NIR, 785 nm) to visible (yellow, centered at 570 regions has been demonstrated in the binary solid of condensed chromophores. Microparticles comprising rubrene as a matrix (emitter) and π-extended Pd-porphyrin dopant (sensitizer) mole ratio 1000:1 were obtained by solution casting. Excitation intensity dependence quantum yield (QY) upconverted emission characterized for individual particles under microscope...
The two-photon absorption (2PA) properties of a series dyes containing donor and acceptor groups connected via π-electronic bridge were studied by using femtosecond Z-scan technique. It was found that the nature does not substantially affect measured 2PA intensities. In case substituted azobenzenes decrease strength and/or leads to intensity, effect being greater.
Static polarizabilities and hyperpolarizabilities have been calculated for the furan homologues including (C4H4O), thiophene (C4H4S), selenophene (C4H4Se), tellurophene (C4H4Te), at Hartree−Fock various correlation levels by ab initio molecular orbital methods. The influence of substitution with heavy atoms on properties was examined theoretically. In calculations molecules Se Te atoms, contribution core electrons in estimated using effective potential (ECP) With calculation molecule,...
The second hyperpolarizabilities of bisimidazole- and bistriazole-benzene compounds have been calculated at different levels approximation to unravel the effects diradical character as well charge spin multiplicity. largest are associated with intermediate character, provided positive charging does not compensate for this effect. For neutral bisimidazole compound, singlet species possesses a hyperpolarizability two three times larger than corresponding triplet, demonstrating possibility...