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1.
Ab initio calculations were performed for the three lowest lying states of HO+2. The ground state was found to be a bend 3A″ state. The first excited 1A′ state cannot appropriately be described by a single determinant, therefore a MC SCF calculation was employed. 相似文献
2.
Interpolation formulas are presented to reproduce the rate coefficients for vibrational–translational energy exchange and dissociation for the N + N2 collision process. The original data have been obtained by quasiclassical method in a detailed way, including the effect of molecular rotation. The fitting procedure results are compared with original data and the related error is evaluated. Comparison with global experimental dissociation results is also presented. 相似文献
3.
A contracted Gaussian basis set capable of describing about 63% of the correlation energy of N2 has been used in a detailed configuration-interaction calculation. Second-order perturbation theory overestimated the correlation energy by 23–50% depending on how H0 was chosen. Pair-pair interaction affects the correlation energy by about 20% while quadruple excitations have an 8% effect. 相似文献
4.
In the study of the N20 molecule with an Ih symmetry group, the following methods were applied: 6-31G, 3-21G and STO-3G ab initio and PM3 semiempirical MO methods. Both geometrical optimization and frequency calculations are reported. Results of optimized bond distances (dN---N), first ionization potential, ΔHa, ΔGa and bond energy, for the cases of 6-31G, 3-21G, and PM3 showed that the N20 molecule is a highly stable compound with a delocalized N---N single bonded cluster structure. 相似文献
5.
Ab initio SCF and Cl calculations are reported for the C3 molecule using a basis set of double-zeta plus polarization quality. Potential curves are obtained for the symmetric stretch and bending and antisymmetric stretch vibrational coordinates for the ground and 3σu → l πg3,1Πu excited states of this system in order to calculate the intensity distributions for the associated electronic transitions. The calculated T0 value for the 1Πu ← X?1 ∑+g transition of 3.03 eV is in quite good agreement with the location of the origin of the 4050 Å (3.06 eV) band system in C3, confirming its previous assignment to this electronic transition; the lifetime of the 1Hu upper state is also obtained in the CI treatment. A value of 2.04 eV is calculated for the corresponding 3Πu ← X?1 ∑+g origin, which result in turn suggests that the weak feature starting at 2.10 eV (5900 Å) should be assigned thereto. 相似文献
6.
High pressure vapour-liquid equilibrium data for the C2H6 + N2, C2H4 + N2, C3H8 + N2, and C3H6 + N2 systems are presented. The data are obtained isothermally in the range from 200 K to 290 K. For each point of data, temperature, pressure and liquid and vapour phase mole fractions are measured.Values for the vapour phase mole fractions are calculated from the obtained pressure, temperature and liquid phase mole fractions. The calculated values are compared with the experimental results, and it is found that the average mean deviation between calculated and experimental mole fractions is less than 0.009 for the systems considered in this work. 相似文献
7.
Infrared multiple-photon dissociation of N2H4 and CH3NH2 fluence dependence of the production of NH2
S.V. Filseth J. Danon D. Feldmann J.D. Campbell K.H. Welge 《Chemical physics letters》1979,63(3):615-620
The multiple-photon dissociation of N2H4 and CH3NH2 by pulsed CO2 laser light to produce NH2(X?2BI has been studied using the laser-induced fluorescence detection method. The relative NH2 yield, represented by the fluorescence signal, has been measured as a function of the fluence from the threshold at about 0.1 J/cm2 to about 100 J/cm2, at different CO2-laser lines and at pressures down to 10?4 Torr. 相似文献
8.
Ai-Min Zhu Qi Sun Jin-Hai Niu Yong Xu Zhi-Min Song 《Plasma Chemistry and Plasma Processing》2005,25(4):371-386
An experimental study on the conversion of NO in the NO/N2, NO/O2/N2, NO/C2H4/N2 and NO/C2H4/O2/N2 systems has been carried out using dielectric barrier discharge (DBD) plasmas at atmospheric pressure. In the NO/N2 system, NO decomposition to N2 and O2 is the dominating reaction; NO conversion to NO2 is less significant. O2 produced from NO decomposition was detected by an on-line mass spectrometer. With the increase of NO initial concentration, the concentration of O2 produced decreases at 298 K, but slightly increases at 523 K. In the NO/O2/N2 system, NO is mainly oxidized to NO2, but NO conversion becomes very low at 523 K and over 1.6% of O2. In the NO/C2H4/N2 system, NO is reduced to N2 with about the same NO conversion as that in the NO/N2 system but without NO2 formation. In the NO/C2H4/O2/N2 system, the oxidation of NO to NO2 is dramatically promoted. At 523 K, with the increase of the energy density, NO conversion increases rapidly first, and then almost stabilizes at 93–91% of NO conversion with 61–55% of NO2 selectivity in the energy density range of 317–550 J L−1. It finally decreases gradually at high energy density. A negligible amount of N2O is formed in the above four systems. Of the four systems studied, NO conversion and NO2 selectivity of the NO/C2H4/O2/N2 system are the highest, and NO/O2/C2H4/N2 system has the lowest electrical energy consumption per NO molecule converted. 相似文献
9.
Low-temperature second interaction virial coefficients for HeN2 are reported that fit very well to high-temperature literature data. These experimental data differ remarkably from calculations performed with a recently proposed potential energy surface. 相似文献
10.
配合物[Cu(H2O)(C12H8N2)2].2ClO4的合成、性质及晶体结构 总被引:1,自引:0,他引:1
《化学研究与应用》2001,13(5):506-508
合成了配合物[Cu(H2O)(C12H8N2)2]*2ClO4(C12H8N2为1,10-邻菲咯啉),用元素分析、摩尔电导、红外光谱及电子光谱进行了表征,并测定了配合物的晶体结构.该晶体属单斜晶系,空间群为CC;晶胞参数a=1.9177(2)nm,b=0.81994(0)nm,c=1.62458(14)nm,β=100.104(6)°;V=2.5419(4)nm3,Z=4,F(000)=1300,DC=1.693g/cm3,R=0.0430,wR=0.1195.中心铜(Ⅱ)离子与两个1,10-邻菲咯啉的四个N原子和一个水分子的氧原子配位,形成了一个变形的三角双锥结构. 相似文献
11.
The intermolecular potentials for D2, N2, O2, F2 and CO2 are determined on the basis of the second virial coeffincients, the polarizabilities parallel and perpendicular to the molecular axes, and the electric quadrupole moment. The repulsive parts of the potentials are taken from the corresponding Kihara core-potentials. Effects of the octopolar induction are taken into consideration in a unique way. The potential depends on relative orientations of the two molecules as well as the distance r between the molecular centers. This dependence is shown in graphs. A measure of the anisotropy of the potential depth is 0.72 for CO2 0.36 for D2, and smaller than 0.27 for N2 O2 and F2. The remarkable anisotropy for CO2 and D2 is due to strong electrostatic quadrupole interactions. 相似文献
12.
Iti GuptaMangalampalli Ravikanth 《Tetrahedron》2003,59(32):6131-6139
A series of meso-furyl porphyrins with four different porphyrin cores (N4, N3S, N2S2 and N3O) were synthesized and characterized. The comparison of NMR, optical and fluorescence properties of meso-furyl porphyrins with porphyrins with six-membered aryl groups indicates that electronic properties of porphyrins were changed drastically on the introduction of furyl groups at meso positions. The maximum shifts in spectral bands were observed for meso-furyl porphyrins with N2S2 core. On protonation, the absorption bands of meso-furyl porphyrins were further red shifted. All these changes were ascribed to the possibility of more planarity of the meso-furyl porphyrins due to the small size of the furyl groups which results in extending the π-delocalisation of the porphyrin ring in to the furyl groups. 相似文献
13.
G. Santosh 《Tetrahedron》2007,63(33):7833-7844
Porphyrins with N4, N3S, and N2S2 cores having one, two, three, and four furyl groups at the meso-positions were synthesized by following various methodologies and characterized by using mass spectrometry, NMR spectroscopy, elemental analysis, absorption, and fluorescence spectroscopic techniques. NMR studies indicated that by replacing the meso-aryl groups with meso-furyl groups, the β-pyrrole and β-thiophene protons of porphyrins experienced considerable downfield shifts, supporting the alteration of π-delocalization of porphyrins on the introduction of meso-furyl groups. The absorption and emission bands of porphyrins experienced red shifts on the introduction of meso-furyl groups and the magnitude of red shifts vary linearly with the number of meso-furyl groups. Thus, the spectral studies supported a systematic alteration in spectral properties on successive introduction of meso-furyl groups. 相似文献
14.
15.
Isochoric PVTx measurements have been performed for the binary system of nitrous oxide + CH3F (R41), +CH2F2 (R32), and +CHF3 (R23) using a new experimental set-up. The experiments covered both the two-phase region and the superheated vapor region and were performed within the temperature range 214–358 K and within a pressure range from 270 to 5600 kPa. Data have been collected for not less than four compositions for each system. The vapor–liquid equilibrium data were derived correlating the experimental data by means of the Carnahan–Starling–De Santis equation of state. The studied systems show a positive deviation from the Raoult's law. The results obtained were compared with the Burnett PVTx data. The two methods showed a mutual consistency within an acceptable margin of error. No other experimental PVTx data were found in the literature for these binary systems. 相似文献
16.
Products of the N2(A) + O2 reaction were measured in a discharge-flow reactor. N2O accounts for only (2 ± 0.5)% of the reaction, contrary to recent reports, and O-atoms for 165 ± 10)% if N2(A) is quantitatively produced from Ar3 with excess N2 This assumption is examined and specific N2(A) + O2 rate parameters are estimated. 相似文献
17.
Daniel D. Konowalow Peter Weinberger Jean-Louis Calais John W.D. Connolly 《Chemical physics letters》1972
The ground 1Σ+g state potential curve for Ne2 is calculated in the SCF × α approximation. The molecule is found to dissociate too slowly and to give no van der Waals minimum. 相似文献
18.
《Chemical physics letters》1996,250(5-6):471-476
The effects of a uniform static electric field on the NMR shielding and magnetizability of H2, N2, HF, and CO are reported. The appropriate defining quantities are the shielding and magnetizability polarizabilities and these are calculated in a mixed numeric-analytic scheme with allowance for electron correlation via third-order Møller-Plesset (MP3) theory or linearized coupled cluster double excitation (L-CCD) theory. This is the first time that these theories have been applied to these properties. Our primary conclusion for the shielding polarizabilities is that, with the exception of H2, the use of coupled cluster theory is necessary to establish the definitive values for these properties because of their extreme sensitivity to electron correlation. For the magnetizability polarizabilities we find the MP3 values to be in better agreement with the L-CCD results than the MP2 values are. 相似文献
19.
Absorption and fluorescent scattering of nitrogen laser radiation by a low-pressure RF laboratory plasma (ne = 1012 cm−3) has been observed for the first negative system of N2+. A 67±1 ns lifetime of N2+ (B 2Σu+) was experimentally measured from the laser-induced fluorescence. In addition, enough collisionally excited N2 (B 3Πg) was produced to observe laser-induced fluorescence for the second positive system of N2. The lifetime of N2 (C 3Πu) was found to be 41±2 ns. The measured lifetimes are in good agreement with published values calculated from theory. 相似文献
20.
Rate constants have been determined for the reaction OH + NO2 (+ N2) → HNO3 (+ N2), using time-resolved resonance absorption to follow the removal of OH radicals produced by flash photolysis of HNO3. The measurements cover the ranges: 220 ? T ? 358 K and 3.2 × 1017 ? [N2] ? 4.0 × 1018 molecule cm?3. 相似文献