A5007055762- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Luminescence and Fluorescent Materials
- Boron Compounds in Chemistry
- Organoboron and organosilicon chemistry
- Organic Light-Emitting Diodes Research
- Crystallography and molecular interactions
- Lipid Membrane Structure and Behavior
- Spectroscopy and Quantum Chemical Studies
- Molecular Sensors and Ion Detection
- Advanced Chemical Physics Studies
- Photochemistry and Electron Transfer Studies
- Supramolecular Self-Assembly in Materials
- Porphyrin and Phthalocyanine Chemistry
- Radiopharmaceutical Chemistry and Applications
- Organic Electronics and Photovoltaics
- Asymmetric Hydrogenation and Catalysis
- Conducting polymers and applications
- Radioactive element chemistry and processing
- Chemical Synthesis and Analysis
- Spectroscopy and Laser Applications
- Nanopore and Nanochannel Transport Studies
- Supramolecular Chemistry and Complexes
- Photoreceptor and optogenetics research
- Magnetism in coordination complexes
Kangwon National University
2016-2025
Fusion (United States)
2016-2021
Government of the Republic of Korea
2016-2021
Institute for Molecular Science
2016-2021
Fusion Academy
2016-2021
Gangwon State University
2019
Northwestern University
2006-2008
The University of Texas at Austin
2001-2007
University of Maryland, College Park
2005
A new bis-pyridinium calix[4]pyrrole derivative is reported. This system forms a non-fluorescent complex upon exposure to the chromenolate anion. The resulting supramolecular ensemble binds pyrophosphate anion with high affinity (Ka = (2.55 ± 0.12) × 107 M−1) in acetonitrile. It exhibits sensitive "turn-on" fluorescence when exposed tetrabutylammonium pyrophosphate, and does so preference other anions, including fluoride phosphate anions.
Three new organic dyes that contain the dithienosilole (DTS) moiety as spacer have been synthesized and their photophysical/electrochemical properties, theoretical calculation dye-sensitized solar cell (DSSC) performance investigated. The overall conversion efficiencies for DSSCs based on these range from 6.73 to 7.50%, comparable a (3–5′-[N,N-bis(9,9-dimethylfluorene-2-yl)phenyl]2,2′-bithiophene-5-yl}-2-cyanoacrylic acid (JK-2)-sensitized device (7.63%), fabricated measured under same...
A dimeric o-carboranyl triarylborane compound (2) with a biphenylene bridge group was prepared and characterized. Also, its solid-state structure determined via X-ray diffraction. Treatment of 2 an excess amount KF in the presence 18-crown-6 formed dimer-type potassium salt, [2·F2][K·18-crown-6]2; fully confirmed by multinuclear NMR spectroscopy. UV–vis titration experiments carried out THF showed that binds fluoride ions binding constant (K) 8.5 × 105 M–1. The linear decline UV/vis...
Four biphenyl- and fluorene-based o-carboranyl compounds, 4-[2-(p-n-butylphenyl)-1-o-carboran-1-yl]biphenyl (1B), 4,4″-bis[2-(p-n-butylphenyl)-1-o-carboran-1-yl]biphenyl (2B), 2-[2-(p-n-butylphenyl)-1-o-carboran-1-yl]fluorene (1F), 2,7-bis[2-(p-n-butylphenyl)-1-o-carboran-1-yl]fluorene (2F), were prepared fully characterized by multinuclear NMR spectroscopy elemental analysis. The crystal structures of 1B 2B, analyzed single-crystal X-ray diffraction, exhibited distinct distortions the...
An efficient transition-metal-free protocol for the hydroboration of aldehydes and ketones (reduction) was developed. The a wide range with pinacolborane (HBpin) under K2CO3 catalyst has been studied. reaction system is practical reliable proceeds extremely mild operationally simple conditions. No prior preparation complex metal required, occurred stoichiometrically. Further, chemoselective reduction over carried out. Moreover, we demonstrated use as an alkenes. operational simplicity,...
Potential of mean force (PMF) profiles a single Na+ or K+ ion passing through cyclic peptide nanotube, cyclo[-(d-Ala-Glu-d-Ala-Gln)2-], in water are calculated to provide insight into transport and understand the conductance difference between these two ions. The PMF obtained by performing steered molecular dynamics (SMD) simulations that based on Jarzynski equality. computed for both ions show barriers around 2.4 kcal/mol at channel entrances exits energy wells middle tube. barriers,...
Facile one-pot synthetic methods for new alkoxo-functionalized heteroleptic cyclometalated Ir(III) compounds have been developed. Nucleophilic substitution of fluorine atoms in [(dfpypy)2Ir(μ-Cl)]2 (dfpypy = 2′,6′-difluoro-2,3′-bipyridine) by a methoxyethanol the presence an ancillary ligand led to formation Ir[(RO)2pypy]2(N∧O) good yields. These distorted octahedral geometry around center with N,N-trans-meridional configuration. They exhibit intense blue yellow phosphorescence (λmax 453–558...
To clarify the relationship between planarity and intramolecular charge transfer (ICT), two o-carboranyl compounds (TCB FCB) containing different ortho-type terphenyl rings, namely, perfectly distorted or planar phenyl were synthesised fully characterised. Although emission spectra of both presented intriguing dual-emission patterns in solution at 298 77 K film state, TCB mostly showed locally excited emission, whereas FCB demonstrated intense corresponding to an ICT transition....
Abstract 9,9′‐Spirobifluorene‐based closo ‐ o ‐carboranyl ( SFC1 and SFC2 ) compounds their nido ‐derivatives were prepared characterized. The two ‐compounds displayed major absorption bands assignable to π–π* transitions involving the spirobifluorene group, as well weak intramolecular charge‐transfer (ICT) between ‐carboranes moieties. exhibited slightly blueshifted resulting from absence of ICT corresponding ‐carborane moieties due anionic character ‐carboranes. While only high‐energy...
Abstract Indium–salen complexes with electron‐donating carbazole (CBZ) groups at positions 4 ( CBZIn1 ) and both 6 CBZIn2 were synthesized characterized to explore the impact of number substituents structural rigidity on their photophysical properties. The single‐crystal structure revealed highly twisted arrangements between CBZ salen moieties, torsion angles 80°–81° 6‐position 45°–47° 4‐position. In center adopted a nearly square‐pyramidal geometry. Both displayed blue fluorescence in...
Electronic decoherence induced only by intramolecular vibrational motions is investigated in a betaine molecule, pyridinium N-phenoxide [4-(1-pyridinio)phenolate], having 60 modes. The analysis based on the nuclear overlap/phase function (NOPF) that appears electronic reduced density matrix. To do so, geometry optimizations and normal-mode ground state first excited are performed. Coherence dissipation times according to alternative approximations obtained, including of role frequency shifts...
A covalently coupled, dimeric tetra-cationic calix[4]pyrrole homodimer bearing anthracene linkers displayed distinctive cooperativity and fluoride selectivity with large positive allosterism.
The series of novel salen-based indium complexes (3-tBu-5-R-salen)In-Me (3-tBu-5-R-salen = N,N'-bis(2-oxy-3-tert-butyl-5-R-salicylidene)-1,2-diaminoethane, R H (1), tBu (2), Br (3), Ph (4), OMe (5), NMe2 (6)) and [(3-tBu-5-NMe3-salen)In-Me](OTf)2 (7; OTf CF3SO3-) have been synthesized fully characterized by NMR spectroscopy elemental analysis. All 1-7 are highly stable in air even aqueous solutions. solid-state structures for 3-5, which were confirmed single-crystal X-ray analysis, exhibit...
Mono-<italic>o</italic>-carborane-substituted pyrenes were prepared and apparently showed the effects of substitution position on their photophysical property.
Abstract Although studies have investigated various N ‐heterocyclic‐based Ir(III)‐cyclometalates that exhibit high efficiency and electrochemical stability, blue‐phosphorescent Ir(III) complexes with further improved blue‐emission purity are needed for use as emitters in organic light‐emitting diodes (OLEDs). Therefore, the preparation comprehensive characterization of a phenyl‐1,2,4‐triazole‐based facial ‐homoleptic iridium(III) complex, TzIr...
Ion current calculations based on Poisson−Nernst−Planck (PNP) theory are performed for a synthetic cyclic peptide nanotube that consists of eight or ten cyclo[(-l-Trp-d-Leu-)4] embedded in lipid bilayer membrane to investigate the ion transport properties nanotube. To explore systems with arbitrary geometries, three-dimensional PNP is implemented using finite difference method. The influence dipolar molecules currents also examined by turning off charges dipoles...
Coarse-grained (CG) molecular dynamics (MD) simulations are performed to study the insertion of cyclic peptide nanotubes into cell membranes and examine whether can function as an ion channel thereby antibacterial agent. To do so, two coarse-grained models for lipid molecules proteins developed by Marrink et al. (J. Phys. Chem. B 2004, 108, 750) Shih 2006, 110, 3674), respectively, were extended modified. These CG verified performing MD all-atom (AA) a nanotube, 8 x...
Three dithienosilole (DTS) derivatives bearing naphthyl segments, 5,5′-dinaphthyl-1,1-dimethyldithienosilol (1), 5,5′-dinaphthyl-1-methyl-1-phenyldithienosilole (2), and 5,5′-dinaphthyl-1,1-diphenyldithienosilol (3), are prepared through Pd(II)-catalyzed cross-coupling using an organoindium reagent as a nucleophile. The molecular structure of 3 is confirmed by single-crystal X-ray analysis. In addition, thermal, photophysical, electrochemical properties for all three compounds systematically...
Abstract A supramolecular host‐guest complex stimulated by lithium cation and fluoride anion, functioning as reliable fluorescence “Off‐On‐Off” switching system has been developed. Nonfluorescent, receptor‐bound fluorophore is exclusively displaced second guest, anion to release thefluorophore that becomes highly fluorescent in guest concentration dependent way. Again, this process completely reversed upon exposure Li + . The entire an excellent model for fluorescence‐based logic system.
Two spiro[acridine-9,9′-fluorene]-based <italic>closo-o</italic>-carboranyl compounds were prepared and they demonstrated the application potential of π-aromatic conjugated <italic>o</italic>-carboranyl as visual sensory materials.
In order to develop a more complete understanding of the limitations mixed quantum-classical simulation methods, origins electronic dephasing are analyzed in simple model condensed phase, namely, spin-boson with an ohmic spectral density. We focus on decay thermally averaged nuclear overlap/phase function (NOPF). Considering strong coupling/high temperature limit, relationship is obtained at short time between rate coherence loss and characteristic classical bath. Using this relationship, we...