scholarly journals Synthesis of C70-fragment buckybowls bearing alkoxy substituents

2020 ◽  
Vol 16 ◽  
pp. 681-690
Author(s):  
Yumi Yakiyama ◽  
Shota Hishikawa ◽  
Hidehiro Sakurai

Buckybowls bearing a C70 fragment having two alkoxy groups were synthesized and their structural and optical properties were investigated by single crystal X-ray analysis and UV–vis spectroscopy. In the synthesis of dioxole derivative 5b, the regioisomer 5c was also produced. The yield of 5c was increased by increasing the reaction temperature, indicating that the rearrangement might involve the equilibrium between the Pd(IV) intermediates through C–H bond activation.

2020 ◽  
Author(s):  
Yumi Yakiyama ◽  
Shota Hishikawa ◽  
Hidehiro Sakurai

Buckybowls of C70 fragment having two alkoxy groups were synthesized and their structural and optical properties were investigated by single crystal X-ray analysis and UV-vis spectroscopy. In the synthesis of dioxole derivative 5b, the regio isomer 5c was also produced. The yield of 5c was increased by increasing the reaction temperature, indicating that the rearrangement might involve the equilibrium between the Pd(IV) intermediates through the C-H bond activation.


2010 ◽  
Vol 1247 ◽  
Author(s):  
Sharul Ashikin Kamaruddin ◽  
Kah-Yoong Chan ◽  
Mohd Zainizan Sahdan ◽  
Dietmar Knipp ◽  
Mohamad Rusop ◽  
...  

AbstractZinc oxide (ZnO) is an emerging optoelectronic material in large area electronic applications due to its various functional behaviors. We report on the fabrication and the characterization of ZnO nanorods. The ZnO nanorods were synthesized using sol-gel hydrothermal technique on oxidized silicon substrates. Different annealing temperatures were explored in the sol-gel hydrothermal synthesis of the ZnO nanorods. In order to investigate the structural properties, the ZnO nanorods were measured using X-ray diffractometer (XRD). The optical properties were measured using ultraviolet-visible (UV-Vis) spectroscopy. The influence of the annealing treatment on the structural and optical properties of the ZnO nanorods will be revealed and discussed in this paper.


2018 ◽  
Vol 74 (11) ◽  
pp. 1487-1494 ◽  
Author(s):  
Brandon Derstine ◽  
Carmen Chamberlain ◽  
Morgan Glover ◽  
Lindsey Porter ◽  
Amanda Eckermann

The triruthenium oxo clusters [Ru3(OAc)6O(L)3]+ and [Ru3(OAc)6O(L)2(CO)] possess unique electronic characteristics that vary based on the ligands L. Here we report an investigation of the structural, electrochemical, and optical properties of clusters with imidazole, benzimidazole, and 4-phenylpyridine ligands. The complexes [Ru3(OAc)6O(L)3]+ [1+ : L = imidazole (im); 2+ : L = benzimidazole (benzim); 3+ : L = 4-phenylpyridine (4PP)] and [Ru3(OAc)6O(L)2(CO)] (1-CO and 3-CO) were synthesized by reaction of either [Ru3(OAc)6O(MeOH)3]+ or [Ru3(OAc)6O(MeOH)2(CO)], respectively, with the corresponding heterocycle. We further discovered that [3]OAc could be reduced to the mixed-valence neutral state 3 by refluxing the complex under nitrogen in methanol. Single-crystal X-ray structure analysis of hexa-μ2-acetato-μ3-oxido-tris(1H-imidazole)triruthenium hexafluorophosphate acetonitrile hemisolvate, [Ru3(C2H3O2)6O(C3H4N2)3]PF6·0.5CH3CN, [1]PF6 , hexa-μ2-acetato-carbonylbis(1H-imidazole)-μ3-oxido-triruthenium methanol monosolvate, [Ru3(C2H3O2)6O(C3H4N2)(CO)]·CH3OH, 1-CO, hexa-μ2-acetato-μ3-oxido-tris(4-phenylpyridine)triruthenium pentahydrate, [Ru3(C2H3O2)6O(C11H9N)3]·5H2O, 3, and hexa-μ2-acetato-carbonyl-μ3-oxido-bis(4-phenylpyridine)triruthenium methanol monosolvate, [Ru3(C2H3O2)6O(C11H9N)2(CO)]·CH3OH, 3-CO, show the expected triruthenium μ3-oxo core and N-coordination of the ligands. Cyclic voltammetry revealed quasi-reversible and irreversible redox couples in [1]PF6 , 1-CO, and [2]PF6 , while [3]PF6 and 3-CO exhibit reversible redox couples. The optical properties of these richly colored species were investigated using UV–Vis spectroscopy.


2017 ◽  
Vol 268 ◽  
pp. 13-17 ◽  
Author(s):  
M.N. Ami Hazlin ◽  
Mohamed Kamari Halimah ◽  
Farah Diana Mohammad ◽  
M.F. Faznny ◽  
Shahrim Mustafa Iskandar

The glass samples of zinc borotellurite glass doped with dysprosium nanoparticles with chemical formula TeO20.7B2O30.30.7ZnO0.31-xDy2O3x (where x= 0.01, 0.02, 0.03, 0.04 and 0.05 molar fraction) have been fabricated by using melt quenching technique. In this study, the structural and optical properties of the zinc borotellurite glass doped with dysprosium nanoparticles were characterized by using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and UV-Vis spectroscopy. From the XRD, the amorphous nature of the glass samples has been confirmed. The infrared spectra revealed four obvious bands which are assigned for BO3, BO4 and TeO4 vibrational groups. The direct and indirect optical band gap, as well as Urbach energy, was calculated through absorption spectra obtained from UV-Vis spectroscopy. From the spectra, it is observed that both direct and indirect optical band gap decreases as the concentration of dysprosium nanoparticles increase. Other than that, the Urbach energy is observed to have an inverse trend with the optical band gap. The Urbach energy is increases as the concentration of dysprosium nanoparticles increases.


2016 ◽  
Vol 12 (3) ◽  
pp. 4394-4399
Author(s):  
Sura Ali Noaman ◽  
Rashid Owaid Kadhim ◽  
Saleem Azara Hussain

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and Silicon  substrates  by  thermal evaporation technique.  X-ray diffraction pattern of  pure SnO2 and SnO2:In thin films annealed at 650oC and the results showed  that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pure  SnO2 and  Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.  Optical properties such as  Transmission , optical band-gap have been measured and calculated.


2015 ◽  
Vol 33 (4) ◽  
pp. 714-718 ◽  
Author(s):  
Neeraj K. Mishra ◽  
Chaitnaya Kumar ◽  
Amit Kumar ◽  
Manish Kumar ◽  
Pratibha Chaudhary ◽  
...  

AbstractA nanocomposite of 0.5SnO2–0.5Al2O3 has been synthesized using a sol-gel route. Structural and optical properties of the nanocomposite have been discussed in detail. Powder X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray diffraction spectroscopy confirm the phase purity and the particle size of the 0.5SnO2–0.5Al2O3 nanocomposite (13 to 15 nm). The scanning electron microscopy also confirms the porosity in the sample, useful in sensing applications. The FT-IR analysis confirms the presence of physical interaction between SnO2 and Al2O3 due to the slight shifting and broadening of characteristic bands. The UV-Vis analysis confirms the semiconducting nature because of direct transition of electrons into the 0.5SnO2–0.5Al2O3 nanocomposites.


2014 ◽  
Vol 989-994 ◽  
pp. 656-659
Author(s):  
Ping Cao ◽  
Yue Bai

Al co-doped ZnCoO thin film has been prepared by a sol-gel method. The structural and optical properties of the sample were investigated. X-ray diffraction and UV absorption spectroscopy analyses indicate that Al3+ and Co2+ substitute for Zn2+ without changing the wurtzite structure. With the Al doping, the visible emission increased and the UV emission decreased, which is attributed to the increase of O vacancies and Zn interstitials.


2021 ◽  
Author(s):  
Yanchun Zhang ◽  
Aimin Sun ◽  
Zhaxi Suonan

Abstract Different complexing agents were used to prepare Ni-Mg-Zn ferrite with the composition formula Ni0.2Mg0.2Zn0.6Fe2O4 via sol-gel method, which included citric acid, oxalic acid, egg white and EDTA. The Ni0.2Mg0.2Zn0.6Fe2O4 ferrite with no complexing agent was also prepared as a comparison. The chemical phases of samples were analyzed by the X-ray diffraction (XRD), which indicated that samples had spinel phase structure. The lattice constants of samples are in the range of 8.3980 ~ 8.4089 Å. The composition and structure were further studied by fourier transform infrared spectroscopy (FTIR). There were two typical characteristic bands related to the stretching vibrations of spinel ferrite in FTIR spectra. Scanning electron microscope (SEM) micrographs and transmission electron microscope (TEM) images showed that the particles have the shape of spherical cube. Energy dispersive spectrometer (EDS) analyzed the elements and ingredients of samples, which included Ni, Mg, Zn, Fe and O. X-ray photoelectron spectroscopy (XPS) is used to examine further the elemental composition and chemical state of sample prepared with EDTA as complexing agent. The optical properties of samples were investigated by photoluminescence spectra and UV-Vis spectroscopy. Vibrating sample magnetometer (VSM) was used to characterize magnetic properties, hysteresis loops revealed the ferrimagnetism behavior of prepared samples.


2000 ◽  
Vol 650 ◽  
Author(s):  
Eduardo J. Alves ◽  
C. Liu ◽  
Maria F. da Silva ◽  
José C. Soares ◽  
Rosário Correia ◽  
...  

ABSTRACTIn this work we report the structural and optical properties of ion implanted GaN. Potential acceptors such as Ca and Er were used as dopants. Ion implantation was carried out with the substrate at room temperature and 550 °C, respectively. The lattice site location of the dopants was studied by Rutherford backscattering/channeling combined with particle induced X-ray emission. Angular scans along both [0001] and [1011] directions show that 50% of the Er ions implanted at 550 oC occupy substitutional or near substitutional Ga sites after annealing. For Ca we found only a fraction of 30% located in displaced Ga sites along the [0001] direction. The optical properties of the ion implanted GaN films have been studied by photoluminescence measurements. Er- related luminescence near 1.54 μm is observed under below band gap excitation at liquid helium temperature. The spectra of the annealed samples consist of multiline structures with the sharpest lines found in GaN until now. The green and red emissions were also observed in the Er doped samples after annealing.


Synlett ◽  
2018 ◽  
Vol 30 (01) ◽  
pp. 54-58 ◽  
Author(s):  
Timothy Swager ◽  
Cagatay Dengiz ◽  
You-Chi Wu

We report the synthesis and characterization of iptycene–naphthazarin dyes by using a sequential Diels–Alder approach. The tautomerization of naphthazarin was used as the key step in the synthesis, with structures confirmed by single-crystal X-ray and NMR analysis. The systematic trends in electronic properties were investigated by UV/Vis spectroscopy. BF2 complexes of the dyes were prepared by reaction with BF3·OEt2 in CH2Cl2.


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