593-51-1Relevant articles and documents
Nitrosyl Complexes of Molebdenum and Tungsten. Part 15. Iodo(monoalkylamido)nitrosylmolybdenum Complexes, some Related Tungten Compounds, and the Crystal and Molecular Structure of Ethylamido(iodo)nitrosylmolybdenum
McCleverty, Jon A.,Rae, A. Elizabeth,Wotochowicz, Iwona,Bailey, Neil A.,Smith, John M. A.
, p. 429 - 438 (1982)
The complexes (NO)I(Y)> (Y=NMe2 or NHR, where R=H, Me, Et, nPr, iPr, nBu, tBu, C6H11, C3H5, or CH2Ph) and (NO)Br(Y)> (Y=H, iPr, or CH2Ph) have been prepared by treatment of the species where Y=I(Mo) or Br(W) with ammonia primary amines, and NHMe2 respectively.Reaction of HB(3,5-Me2C3HN2)3>(NO)I(NH2)> with HCl, and with acetone in the presence of NEt3 respectively, gives (NO)Cl2> and Cl, and (NO)I(N=CMe2)>*Me2CO.The crystal and molecular structure of (NO)I(NHEt)>, as a di-isopropyl ether solvate, has been determined by X-ray diffraction methods using counter data and refined by block-diagonal least-squares procedures, to R=0.0534 for 3150 reflections.The molecule is six co-ordinate, with a linear Mo-N-O group, and a short Mo-NHEt bond.Crystals are monoclinic with a=40.00(3), b=12.751(10), c=10.60(3) angstroem.β=97.23(2) deg, space group P21/a, and Z=8.
P-P orbital interaction: via magnesium isovalent doping enhances optoelectronic properties of halide perovskites
Qian, Feng,Gong, Jue,Hu, Mingyu,Ge, Chunyu,Padture, Nitin P.,Zhou, Yuanyuan,Feng, Jing
, p. 15639 - 15642 (2020)
p-p orbital interaction through Mg(ii) isovalent doping in methylammonium lead chloride perovskite significantly enhances the electronic properties while not affecting the optical bandgap. This chemical behaviour shows promising applications to optoelectr
Low-temperature photoluminescence spectroscopy of CH3NH3PbBrxCl3-x perovskite single crystals
Xu, Qiang,Shao, Wenyi,Zhang, Xinlei,Liu, Jun,Ouyang, Xiaoping,Tang, Xiaobin,Jia, Wenbao
, p. 185 - 190 (2019)
Organic-inorganic halide perovskite (OIHP) has attracted tremendous attention due to its potential applications in optoelectronics such as light emitting device and photodetector. Here, we have grown high quality CH3NH3PbBrx/su
Visual clarity methylammonium lead trichloride perovskite single crystals for X and gamma rays protection
Xu, Qiang,Shao, Wenyi,Li, Yang,Zhang, Hang,Ouyang, Xiao,Zhang, Xinlei,Nie, Jing,Ouyang, Xiaoping,Liu, Bo
, (2019)
Ionization radiation photons such as X-ray and gamma ray have been widely applied in the nuclear power industry, medical imaging, scientific research, and aerospace exploration. Developing a protective material with excellent shielding properties and clear visibility is an urgent demand in order to protect people who are working in a radiation environment. Hence, we present a highly efficient radiation shielding material based on lead halide organic-inorganic perovskite single crystals with visual clarity, high efficiency and attenuation coefficient, and thin half-value layer. Our results indicate that the shielding performances (mass attenuation coefficients, effective atomic numbers and half value layer) of the perovskite crystals are at least one order higher than the current commercial products, such as Bone-equivalent plastic, Polyethylene terephthalate, and colorless glass. In addition, physical properties (density), and optical properties (transmission, refractive index), can be slightly tuned by the dopant Br concentration in crystals. The present results demonstrate that the organic-inorganic perovksite single crystals are optimized for high attenuation radiation shielding materials with visual clarity.
Stereodynamics of Diethylmethylamine and Triethylamine
Bushweller, C. Hackett,Fleischman, Stephen H.,Grady, Gilbert L.,McGoff, Paul,Rithner, Christopher D.,et al.
, p. 6224 - 6236 (1982)
Diethylamine is the simplest acyclic trialkylamine that possesses the requisite symmetry that allows, in principle, the direct observation of both nitrogen inversion and isolated nitrogen-carbon bond rotation using 1H dynamic nuclear magnetic resonance (DNMR) spectroscopy.DNMR studies of diethylmethylamine and two deuterated derivatives complemented by empirical force-field calculations reveal a comprehensive picture of the stereodynamics of this representative acyclic trialkylamine.The DNMR studies show clear evidence for pyramidal inversion at nitrogen.In addition to nitrogen inversion, the results also speak for several "families" of rotamers for diethylmethylamine that undergo very rapid, DNMR-invisible intrafamily conformational exchange via isolated N-CH2 rotation while also undergoing higher barrier DNMR-visible interfamily exchange also via isolated N-CH2 rotation.The DNMR-visible N-CH2 rotation processes involve CCH3/N-alkyl eclipsing in the transition state while the DNMR-invisible processes involve CCH3/lone pair eclipsing.Although the symmetry of triethylamine precludes the DNMR-observation of nitrogen inversion, (1)H DNMR evidence for restricted N-CH2 rotation and empirical force-field calculations reveal stereodynamics for triethylamine that are highly analogous to diethylmethylamine.
Crystal Growth, Structural Phase Transitions, and Optical Gap Evolution of CH3NH3Pb(Br1-xClx)3 Perovskites
Alvarez-Galván,Alonso,López,López-Linares,Contreras,Lázaro,Fauth,Martínez-Huerta
, p. 918 - 924 (2019)
Chemically tuned inorganic-organic hybrid halide perovskites based on bromide and chloride anions CH3NH3Pb(Br1-xClx)3 have been crystallized and investigated by synchrotron X-ray diffraction (SXRD), scanning electron microscopy, and UV-vis spectroscopy. CH3NH3PbBr3 and CH3NH3PbCl3 experience successive phase transitions upon cooling, which are suppressed for intermediate compositions probably due to compositional disorder. For CH3NH3PbCl3, a transient phase, formerly described as tetragonal, was identified at 167.5 K; the analysis of SXRD data demonstrated that it is indeed orthorhombic, with space group Pnma, and a ≈ 2ap; b ≈ 2ap; c ≈ 2ap (ap is the ideal cubic perovskite unit-cell parameter). The band gap engineering brought about by the chemical management of CH3NH3Pb(Br1-xClx)3 perovskites can be controllably tuned: the gap progressively increases with the concentration of Cl ions from 2.2 to 2.9 eV, and shows a concomitant variation with the unit-cell parameters of the cubic phases at 295 K. This study provides an improved understanding of the structural and optical properties of the mixed CH3NH3Pb(Br1-xClx)3 perovskites.
Deoxygenation of primary amides to amines with pinacolborane catalyzed by Ca[N(SiMe3)2]2(THF)2
Gong, Mingliang,Guo, Chenjun,Jiang, Linhong,Luo, Yunjie,Yu, Chong
supporting information, p. 1201 - 1206 (2021/05/29)
Deoxygenative reduction of amides is a challenging but favorable synthetic method of accessing amines. In the presence of a catalytic amount of Ca[N(SiMe3)2]2(THF)2, pinacolborane (HBpin) could efficiently reduce a broad scope of amides, primary amides in particular, into corresponding amines. Functional groups and heteroatoms showed good tolerance in this process of transformation, and a plausible reaction mechanism was proposed.
Reduction of Amides to Amines with Pinacolborane Catalyzed by Heterogeneous Lanthanum Catalyst La(CH2C6H4NMe2- o)3@SBA-15
Guo, Chenjun,Zhang, Fangcao,Yu, Chong,Luo, Yunjie
supporting information, p. 13122 - 13135 (2021/08/31)
Hydroboration of amides is a useful synthetic strategy to access the corresponding amines. In this contribution, it was found that the supported lanthanum benzyl material La(CH2C6H4NMe2-o)3@SBA-15 was highly active for the hydroboration of primary, secondary, and tertiary amides to amines with pinacolborane. These reactions selectively produced target amines and showed good tolerance for functional groups such as -NO2, -halogen, and -CN, as well as heteroatoms such as S and O. This reduction procedure exhibited the recyclable and reusable property of heterogeneous catalysts and was applicable to gram-scale synthesis. The reaction mechanisms were proposed based on some control experiments and the previous literature. This is the first example of hydroborative reduction of amides to amines mediated by heterogeneous catalysts.
Blue-emitting NH4+-doped MAPbBr3perovskite quantum dots with near unity quantum yield and super stability
Deng, Jidong,Xun, Jiao,Qin, Youcheng,Li, Ming,He, Rongxing
supporting information, p. 11863 - 11866 (2020/10/13)
Novel NH4+-doped MA1?x(NH4)xPbBr3perovskite quantum dots were synthesized at room temperature. The introduction of NH4+results in larger lattice formation energy and b
Solvent-free, solid phase synthesis of hybrid lead halide perovskites with superior purity
-
Page/Page column 6-7, (2020/12/30)
A method of synthesizing a mixed-halide perovskite is disclosed herein. The method includes the steps of mixing a first single-halide perovskite and a second single-halide perovskite to form a solid phase mixture and heating the solid phase mixture at a temperature below a first decomposition temperature of the first single-halide perovskite and below a second decomposition temperature of the second single-halide perovskite for a time sufficient to form the mixed-halide perovskite. During the mixing, the first and second single-halide perovskite are both in the solid phase. A mixed-halide perovskite made according to the method is also disclosed herein. The mixed-halide perovskite is free of amorphous and/or semicrystalline phases. The mixed-halide perovskite can be utilized in a photovoltaic cell in a solar panel.
