共查询到20条相似文献,搜索用时 31 毫秒
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利用ab initio 量子化学方法研究了自旋禁阻的传能反应O(1D)+CO2(1Σ+g)→O(3P)+CO2(1Σ+g)的反应机制, 通过中间化合物CO3的单、三重态的势能面交叉点的确认, 证明了中间物传能机理的可行性. 同时计算了交叉点处的自旋-轨道偶合和面间跃迁几率, 进一步证明了中间化合物CO3的形成在传能过程中的重要作用. 相似文献
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Steric effect in the energy transfer reaction of N(2)(A(3)Σ(u)(+)) + NO(X(2)Π) → NO(A(2)Σ(+)) + N(2)(X(1)Σ(g)(+)) has been studied under crossed beam conditions at a collision energy of ~0.07 eV by using an aligned N(2)(A(3)Σ(u)(+)) beam prepared by a magnetic hexapole. The emission intensity of NO(A(2)Σ(+)) has been measured as a function of the magnetic orientation field direction (i.e., alignment of N(2)(A(3)Σ(u)(+))) in the collision frame. A significant alignment effect on the energy transfer probability is observed. The shape of the steric opacity function turns out to be most reactive at the oblique configuration of N(2)(A(3)Σ(u)(+)) with an orientation angle of γ(v(R)) ~ 45° with respect to the relative velocity vector (v(R)), which has a good correlation with the spatial distribution of the 2pπ(g)* molecular orbital of N(2)(A(3)Σ(u)(+)). We propose the electron exchange mechanism in which the energy transfer probability is dominantly controlled by the orbital overlap between N(2)(2pπ(g)*) and NO(6σ). 相似文献
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《Chemical physics》1987,115(3):423-432
The dissociation energy (De) for the O3(X̃ 1A1) → O2(X 3Σ−g) + O(3P) process is computed using MC SCF, CI, MBPT, and CCD methods. A full-valence MC SCF calculation utilizing a [9s5p3d1f/5s3p2d1f] basis set yields a De value of 0.43 eV, far below the experimental value of 1.13 eV, demonstrating the importance of correlation effects involving non-valence orbitals. A CI calculation in the same basis set allowing for all single and double excitations from three-reference configuration yields a De value of 0.72 eV. This value is increased to 1.06 eV when the Davidson correction is included. When the number of reference configurations is increased to eight, the resulting CI calculation gives a De value of 0.82 eV prior to the Davidson correction and 1.10 eV after this correction. 相似文献
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Kravchenko E. A. Kargin Yu. F. Egorysheva A. V. Buslaev Yu. A. 《Russian Journal of Coordination Chemistry》2001,27(8):542-547
It was earlier found from nuclear quadrupole resonance (NQR) measurements and computer modeling that -Bi2O3, Bi3O4Br and mixed oxides Bi2O3· 2Al2O3, Bi2O3· 2Ga2O3, Bi2O3· 3GeO2, and 2Bi2O3· 3GeO2exhibit local ordered magnetic fields from 30 to 200 G. It thus follows that these compounds are not diamagnets in a conventional sence of the word. With the aim of revealing previously unknown magnetic properties in bismuth(III) oxide-based Main Group element compounds, the mixed bismuth–boron oxides 2Bi2O3· B2O3, 3Bi2O3· 5B2O3, and Bi2O3· 3B2O3were prepared and studied using 209Bi NQR. The quadrupole interactions of the 209Bi nuclei and their electronic environment were studied, the crystallochemical features of the compounds were discussed, and the conformity of the 209Bi results to the X-ray structure data was verified. The preliminary tests in the field of a permanent magnet showed that the resonance intensities increase in external magnetic fields, indicating that a magnetism of unknown nature develops in the titled compounds. It was found reasonable to continue studies of the magnetic properties of these compounds using single-crystal 209Bi NQR in external magnetic fields. 相似文献
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V. V. Klepov E. V. Peresypkina L. B. Serezhkina A. V. Virovets V. N. Serezhkin 《Russian Journal of Inorganic Chemistry》2012,57(10):1341-1347
Crystals of [Cr3O(CH3COO)6(H2O)3][UO2(CH3COO)3]·3H2O (I) were synthesized for the first time and studied by X-ray crystallography. The crystals of I are orthorhombic: a = 8.3561(3) ?, b = 16.8421(5) ?, c = 25.7448(9) ?, V = 3623.2(2) ?3, space group P212121, Z = 4, R = 0.0409. The structure is composed of trinuclear [Cr3O(CH3COO)6(H2O)3]+ complexes and mononuclear [UO2(CH3COO)3]? complexes classified with crystal-chemical groups A3M3B 6 2 M 3 1 (A = Cr3+, M3 = O2?, B2 = CH3COO?, M1 = H2O) and AB 3 01 (A = UO 2 2+ , B01 = CH3COO?), respectively. The complexes are bound to each other by electrostatic interactions and hydrogen bonds involving outer-sphere water molecules. The results of IR spectroscopic study of I are in good agreement with the structural data for the crystal. 相似文献
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本文系统研究了冰晶石熔体中添加钇族稀土碳酸盐即2.7NaF·AlF3(7Wt%CaF2)-Al2O3-YM2O3体系的一系列物理化学性质。 应用最优化设计原理,研究了该体系的初晶温度、表面张力、密度、粘度和电导率,分别得到了表征该体系初晶温度、粘度与Al2O3、YM2O3浓度关系的回归方程以及该体系表面张力、密度、电导率与Al2O3、YM2O3浓度和温度关系的回归方程。 相似文献
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Lomonova E. E. Agarkov D. A. Borik M. A. Eliseeva G. M. Kulebyakin A. V. Kuritsyna I. E. Milovich F. O. Myzina V. A. Osiko V. V. Chislov A. S. Tabachkova N. Yu. 《Russian Journal of Electrochemistry》2020,56(2):118-123
Russian Journal of Electrochemistry - The effects of the Y2O3 and Yb2O3 co-doping impurities on the transport characteristics and stabilization of the cubic phase in solid solutions based on... 相似文献
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Nidhuban Deb 《Journal of Thermal Analysis and Calorimetry》2013,114(1):261-267
Strontium(II)diaquatris(oxalato)lanthanate(III)unidecahydrate, Sr3[La(C2O4)3(H2O)2]2·11H2O, has been synthesized and characterized by elemental, IR and electronic spectral studies. Thermal studies (TG, DTG and DTA) in air showed that all the crystal and coordinated water molecules are removed at ca. 225 °C. The final end product at 1,000 °C was shown to be a mixture of mainly SrCO3, Sr3La4O9 and La2Sr2O5 along with oxides and carbides of both the metal, through the formation of an intermediate mixture of likely SrC2O4 and La2(C2O4)2.8 at 282 °C, and SrCO3 and La2O(CO3)2 at 540 °C. The multi-step dehydration and decomposition of the compound has been explored from the DSC study in nitrogen up to 670 °C, and the evaluated kinetic parameters are discussed. 相似文献
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采用密度泛函B3LYP方法, O和N用6-311+G*基组, Au+用赝势基组(8s7p6d)/[6s5p3d], 研究了Au+(1S, 3D)离子和N2O(1Σ+)分子的反应机理. 报道了在基态单重态和激发三重态势能面上各反应物、中间体和过渡态的构型特征及能量. 结果表明, 两个主反应通道Au+(1S)+ N2O(1Σ+)→1NA-Complex-1→1NA-TS1→1NA-Complex-2→1NA-Crossing→[3OAuNN]+和Au+(1S)+ N2O(1Σ+)→1NB-Complex→1NB-Crossing→[AuNN(1Σ+)]++O(3P)都需经过反应交叉势能面, 出现“系间窜越”. 用内禀坐标单点计算垂直激发态的方法确定了势能面交叉点, 并用含时密度泛函TD-B3LYP方法进一步探讨了自旋翻转机理. 相似文献
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Peter Švančárek Peter Schwendt Jozef Tatiersky Ivana Smatanová Jaromír Marek 《Monatshefte für Chemie / Chemical Monthly》2000,131(2):145-154
Summary. Oxo peroxo glycolato complexes of vanadium(V) (M
2[V2O2(O2)2(C2H2O3)2]ċnH2O (n=0, 1; M=NBu4
+ (1), K+ (2), NH4
+ (3), Cs+ (4), NPr4
+ (5)) as well as (NBu4)2[V2O4(C2H2O3)2]ċ H2O (6) have been prepared and characterized by spectroscopic methods. X-Ray structure analysis of 1 revealed the presence of dinuclear [V2O2(O2)2(C2H2O3)2]2− anions with a (chemical structure) bridging core and six coordinated vanadium(V) atoms in a distorted pentagonal pyramidal
array.
Received July 12, 1999. Accepted (revised) October 28, 1999 相似文献
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《Chemical physics letters》1987,140(5):476-482
Experimental evidence is provided to show that the Ar2(3Σ+u) excimer is photoionized by absorption of light at 308 nm. This direct photoionization of Ar2(3Σ+u) was used to measure the distribution of atomic states belonging to the Ar(3p54p) electronic manifold produced in dissociative recombination of Ar2+(2Σu+) at atmospheric pressure. It was found that electronically excited states, Ar(2p2) and Ar(2p10), accounted for 96% of the excited state population of the Ar(3p54p) configuration produced in dissociative recombination. The Ar2(3Σu+) state is also photodissociated directly at 308 nm producing electronically excited Ar atoms more energetic than the Ar(3p54p) configuration. 相似文献
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Yu. N. Mikhailov I. M. Orlova R. N. Shchelokov Yu. E. Gorbunova Zh. V. Akhmerkina L. B. Serezhkina V. N. Serezhkin 《Russian Journal of Inorganic Chemistry》2006,51(3):402-407
The single crystals of K3[UO2(C2O4)2(NCS)] · 3H2O were studied by X-ray diffraction. The compound crystallizes in the monoclinic system, space group P21/n, Z = 4, a = 10.673 Å, b = 12.041 Å, c = 13.856 Å, β = 110.18°, R = 0.0290. The basic structural units of the crystals of I are the island complex groups [UO2(C2O4)2NCS]3? corresponding to the crystal-chemical group AB01 2M1 (A = UO 2 2+ , B01 = C2O 4 2? , M1 = NCS?) of uranyl complexes and connected into a three-dimensional framework through electrostatic interactions and through hydrogen bonds involving potassium ions and water molecules. 相似文献
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Albinas Pigaga Remigijus Juškėnas Algis Selskis 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1237-1243
This article deals with the insoluble compounds, formed in CuSO 4 -(NH 4 ) 4 P 2 O 7 -H 2 O system. The solutions were analyzed by means of chemical analysis, the precipitate--by means of x-ray diffraction, chemical and thermal analysis, and FTIR spectroscopy. We have established that at least three poorly soluble compounds can form in the system CuSO 4 -(NH 4 ) 4 P 2 O 7 -H 2 O. Their chemical formulae are Cu 2 P 2 O 7 ;5H 2 O and polymorphic Cu 3 (NH 4 ) 2 (P 2 O 7 ) 2 ;3H 2 O. The first modification is most stable when |Cu + P 2 O 7 | = 0.25 M ( n = 1.0), and, in a matter of days, Dimorph A transforms to Dimorph B, which has not been described in any publications. 相似文献
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采用高温固相反应法,合成了一系列不同组份的磷光体,测定了它们的振动光谱.结果表明,随着Al/B比的减小,在1100~1000cm-1的区域内的振动光谱没有明显变化,铕离子不可能进入Al18B4O33的晶格中;振动光谱的背底升高,非晶相逐渐增加.研究了Al2O3-B2O3-Eu2O3中Eu3+离子的光谱特性,发现随着Al/B比的减少,Eu3+离子的存在相由晶相逐渐向非晶相转化。在非晶相中,Eu3+离子的声子伴带表明电子与声子的耦合强度随着Al/B比的减少而减小,Eu3+离子的发射强度相应的增加,这与多声子弛豫的理论一致. 相似文献
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YU Yang LIU Dan HU Wei-wei LI Jia PENG Yu ZHOU Qi YANG Fen LI Guang-hua SHI Zhan FENG Shou-hua 《高等学校化学研究》2012,28(2):186-190
Three metal molybdate hydrates,Fe(H2O)2(MoO4)2·H3O(FeMo),NaCo2(MoO4)2(H3O2)(CoMo)and Mn2(MoO4)3·2H3O(MnMo),were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray... 相似文献
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测定了三元体系DyCl3-CdCl2-H2O和四元体系DyCl3-CdCl2-HCl(~8%)-H2O(25℃)的相平衡溶度数据,绘制了相应的溶度图.三元体系和四元体系均为复杂体系且均有新化合物9CdCl2·2DyCl3·29H2O生成.对化合物9CdCl2·2DyCl3·29H2O进行了XRD、TG-DTG和荧光光谱研究,并对X-射线粉末衍射数据进行了指标化.该化合物属单斜晶系,具有一定的荧光强度,在50~242℃分3步失去结晶水. 相似文献