- Highly Ordered, Self-Assembled Monolayers of a Spin-Crossover Complex with In-Plane Interactions
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For the technological integration of molecular switches in electronic devices, self-assembling nanomaterials of such switches are highly sought after. The syntheses of a new tetrapyridyl ligand bearing a C12 alkyl chain and two N?H bridges (compound 1) and of its iron(II) complex [Fe(1)(NCS)2] (compound 2), are described. Magnetic susceptibility data for bulk samples of 2 confirmed their gradual spin-crossover properties. The self-assembly of 1 and 2 on highly ordered pyrolytic graphite surfaces (HOPG) was investigated by Scanning Tunneling Microscopy (STM). Both compounds 1 and 2 formed ordered monolayers after deposition by drop casting. The patterns of the two compounds are very different, which is attributed to the fundamentally different hydrogen bonding networks before and after coordination of Fe(NCS)2 to the tetradentate chelate. Two possible models for the self-assembly of 1 and 2 are provided. This work suggests that it is possible to design molecular switches that self-assemble on surfaces in highly ordered monolayer films. This is a significant step in the development of spin-switching materials, which may streamline the integration of molecular switches in for example memory and sensing devices.
- Bonnet, Sylvestre,Spa, Silvia,Zheng, Sipeng,van Geest, Erik P.,van Ruitenbeek, Jan M.
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p. 2814 - 2821
(2021/07/07)
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- Strong Visible-Light-Absorbing Cuprous Sensitizers for Dramatically Boosting Photocatalysis
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Developing strong visible-light-absorbing (SVLA) earth-abundant photosensitizers (PSs) for significantly improving the utilization of solar energy is highly desirable, yet it remains a great challenge. Herein, we adopt a through-bond energy transfer (TBET) strategy by bridging boron dipyrromethene (Bodipy) and a CuI complex with an electronically conjugated bridge, resulting in the first SVLA CuI PSs (Cu-2 and Cu-3). Cu-3 has an extremely high molar extinction coefficient of 162 260 m?1 cm?1 at 518 nm, over 62 times higher than that of traditional CuI PS (Cu-1). The photooxidation activity of Cu-3 is much greater than that of Cu-1 and noble-metal PSs (Ru(bpy)32+ and Ir(ppy)3+) for both energy- and electron-transfer reactions. Femto- and nanosecond transient absorption and theoretical investigations demonstrate that a “ping-pong” energy-transfer process in Cu-3 involving a forward singlet TBET from Bodipy to the CuI complex and a backward triplet-triplet energy transfer greatly contribute to the long-lived and Bodipy-localized triplet excited state.
- Chen, Kai-Kai,Guo, Song,Li, Xiyou,Liu, Heyuan,Lu, Tong-Bu,Zhang, Zhi-Ming
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supporting information
p. 12951 - 12957
(2020/05/29)
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- RARE EARTH METAL COMPLEX HAVING PHENANTHROLINE COMPOUND AS LIGAND
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The present invention provides a rare earth metal complex represented by the following formula (I).
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Page/Page column 37
(2012/10/07)
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- PHENANTHROLINE DERIVATIVES AND THEIR USE AS LIGANDS
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The present invention provides a novel compound having a phenanthroline structure represented by the following formula (I) or a salt thereof useful as a ligand of an analytical marker using fluorescence.
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Page/Page column 26-27
(2011/04/18)
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- LUMINESCENT SILVER COMPLEXES
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An luminescent device material which is inexpensive and exhibits excellent durability in the presence of oxygen can be provided using a luminescent silver complex which has an organic multidentate ligand, particularly, a luminescent silver complex wherein the organic multidentate ligand is coordinated to a phosphorus atom, a nitrogen atom, an oxygen atom, a sulfur atom, an arsenic atom, an oxygen anion, a nitrogen anion, or a sulfur anion, or a polymer of the luminescent silver complex.
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Page/Page column 43
(2011/09/15)
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- Pyridazine and Pyrrole Compounds, Processes For Obtaining Them and Uses
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The present invention relates to nonlinear oligopyridazine compounds, to processes for obtaining them, to their uses, and also to their reduction to oligopyrroles and to the uses of the pyridazinylpyrrole and oligopyrrole compounds obtained. The invention relates in particular to the uses as medicaments, in particular for treating pathologies such as cancer, bacterial infections or parasitic infections, and also the uses in the materials, environmental, electronics and optics field.
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- Expanded π-electron systems, tri(phenanthro)hexaazatriphenylenes and tri(phenanthrolino)hexaazatriphenylenes, that are self-assembled to form one-dimensional aggregates
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This paper reports the self-assembling and electrochemical nature of hexaazatriphenylene-based electron-deficient heteroaromatics with an expanded π-electron system. The tri(phenanthro)hexaazatriphenylenes (TPHAT-Cs) and tri(phenanthrolino)hexaazatriphenylenes (TPHAT-Ns) were prepared by condensation reactions of the corresponding phenanthrenequinones and phenanthrolinediones, respectively, with hexaaminobenzene. Their electron affinity was indicated from cyclic voltammetry measurements, in which the first reduction potentials were evaluated at around -1.7 V (vs Fc/Fc+) in dichloromethane. In nonpolar and polar solvents and in the film state, the TPHAT-Cs and TPHAT-Ns formed one-dimensional aggregates with an H-type parallel stacking mode. In the MALDI-TOF mass spectra, significant peaks were seen at several multiples of the parent ion up to tetramer aggregates. The 1H NMR spectra indicated a line-broadening effect due to the aggregation. The UV-vis and fluorescence spectra showed a concentration dependence, which is attributed to a dynamic exchange between the monomer and aggregate species. The order of the aggregative nature was estimated from the concentration dependence and the fluorescence quantum yield. By replacement of the peripheral aromatic moieties instead of the phenanthrene (TPHAT-Cs) with the phenanthroline (TPHAT-Ns), the aggregative nature was enhanced.
- Ishi-I, Tsutomu,Hirashima, Ryoichi,Tsutsumi, Naotaka,Amemori, Shogo,Matsuki, Shigeki,Teshima, Yuuki,Kuwahara, Rempei,Mataka, Shuntaro
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experimental part
p. 6858 - 6868
(2010/11/24)
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