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1.
The vertical core– and valence–shell electron excitation and ionization energies of the three title molecules, 1–3, were calculated by density functional theory (DFT) using adequate functional for each type of processes and atoms under study. The inner shells treated were C1s, N1s, S1s, S2s, S2p. Molecular geometry was optimized by DFT B3LYP/6-311 + (d,p). The basis set of triple zeta plus polarization (TZP) Slater-type orbitals was employed for DFT calculations. The ΔSCF method was used to calculate ionization energies. The average absolute deviation (AAD) from experiment of 26 valence-electron ionization energies calculated by DFT for the three molecules 1–3 was 0.14 eV; while that of 24 calculated core-electron binding energies (CEBEs) from experiment was 0.4 eV. Selected core excitation energies were calculated by the multiplet approximation for the three molecules. The AAD of twelve calculated core excitation energies by the multiplet approximation that exclude S2s cases was 0.56 eV. Time-dependent DFT (TDDFT) was employed to calculate the excitation energies and corresponding oscillator strengths of core- and valence-electrons of the molecules. Some selected occupied core orbitals were used to calculate the core-excitation energies with the TDDFT (Sterner–Frozoni–Simone scheme). The core excitation energies thus calculated were in an average error of ca. 28 eV compared to observed values. They were shifted to the value calculated by the multiplet approximation. Convoluted spectra based upon the shifted energies and accompanying oscillator strengths reproduce low-energy region of observed spectra reasonably well, whereas they deviate from experiment in high-energy region. Reasonable agreement between theory and experiment was obtained for the valence electron excitations of the molecules. 相似文献
2.
F. LattanziC. di Lauro M. HermanJ.Vander Auwera 《Journal of Molecular Spectroscopy》2002,216(2):308-314
A detailed investigation of the high-resolution infrared spectrum of ethane revealed the occurrence of features belonging to the hot perpendicular system (ν4+ν8)−ν4 between 1400 and 1510 cm−1. Transition lines of the subbranches with K″ΔK from −7 to 4, exhibiting torsional splittings of several tenths of a cm−1, were observed and measured in this region. The observed line splittings are strongly influenced by the interaction between the ν4+ν8 and 2ν4+ν12 states and change with the values of K″ΔK, depending on the zero-order energy separation of the interacting levels. We found by numerical extrapolation that splittings still occur far from resonance, showing that the intrinsic torsional splittings of the combining states ν4+ν8 and ν4 are quite different. We determined the intrinsic torsional splitting of ν4+ν8 to be less than 0.083 cm−1, compared with 0.236 cm−1 estimated for the ν4 state. This result is in agreement with the expected effects of torsional Coriolis and head-tail coupling and is consistent with previous observations on vibrationally degenerate states of ethane-like molecules. 相似文献
3.
Yan-Hong Cui Wei Quan Tian Ji-Kang Feng De-Li Chen 《Journal of nanoparticle research》2010,12(2):429-438
Among all the 4478 classical isomers of C66, C66(C
s
:0060) with the lowest number of pentagon–pentagon fusions was predicted to be the most stable isomer, followed by isomers
C66(C
2v
:0011) and C66(C
2:0083). The infrared spectra and aromaticity of the most stable isomers were predicted. The relative stabilities of C66 isomers change with charges or doping of metals. The structures and relative stabilities of the most stable metallofullerenes
were delineated and compared with experiment. Sc2@C66(C
2:0083) was predicted to be the most stable metallofullerene, although Sc2@C66(C
2v
:0011) was observed. Charge-transfer from Sc2 to the fused pentagons and the bonding between these two moieties significantly decrease the strain energies caused by the
pair of fused pentagons thereby stabilizing the fullerene cage. 相似文献
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本文在独立电子近似的基础上,根据多重散射自洽场理论方法,计算了C2和C2+,C2-分子(离子)的电子结构,阐明了势形共振能量和上述分子(离子)电子数的关系,结果表明,随着电子数的减少,C原子2s-2p轨道杂化减弱,势形共振的能量将降低(如降低到阈值下,则势形共振消失)。
关键词: 相似文献
6.
V. Malathy Devi C.P. Rinsland R.L. Sams 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(9):1234-1251
Line positions, intensities, Lorentz self- and N2-broadened half-width coefficients have been measured for PQ3, PQ2, PQ1, RQ0, RQ1, RQ2, and RQ3 sub-band transitions in the ν9 fundamental band of 12C2H6. A multispectrum nonlinear least-squares fitting technique was used to fit up to 17 high-resolution (∼0.00156 cm−1), room temperature absorption spectra of pure (99.99% chemical purity) natural sample of ethane and lean mixtures of the high-purity ethane diluted with N2. A Bruker IFS 120HR Fourier transform spectrometer located at the Pacific Northwest National Laboratory (PNNL), in Richland, Washington was used to record the data. A standard Voigt line shape was assumed to fit all the data since no line mixing or other non Voigt line shapes were required to fit any of the spectra used in the analysis. Short spectral intervals (∼2-2.5 cm−1) of all 17 spectra covering a specific PQ or RQ sub-band were fit simultaneously. For the first time in an ethane band, pressure-broadened half-width coefficients were determined for the torsional-split components. However, for better reliability of the retrieved coefficients for the weaker components (transitions with large intensity ratios of 4:1 or 3:1 for most K levels between the strong and weak components), constraints were used such that the half-width coefficients of both torsional-split components for a given J were identical for a specific broadening gas. No pressure-induced shift coefficients were necessary to fit the spectra to their noise level. The present study revealed for the first time the dependence of self- and N2-broadened half-width coefficients upon the J, K quantum numbers of the transitions in ethane. A number of transitions belonging to the ν9+ν4−ν4 and the ν9+2ν4−2ν4 hot bands were also observed in the fitted regions and measurements were made when possible. 相似文献
7.
运用激光拉曼光谱实验和密度泛函理论计算研究了450~1 700 cm-1光谱范围内有机-无机杂化钙钛矿材料(C6H5CH2NH3)2PbBr4的振动模式特性。对比实验所得拉曼光谱和理论计算所得拉曼光谱,发现密度泛函理论计算可以很好的模拟(C6H5CH2NH3)2PbBr4有机部分的分子振动模式。同时通过比较分析密度泛函理论计算和参考文献,对450~1 700 cm-1光谱范围内的拉曼峰的分子振动模式进行了初步的归属,并发现该光谱范围内的拉曼峰主要是由(C6H5CH2NH3)2PbBr4分子中有机部分振动所产生的。 相似文献
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Bradley在1925年所定出KLiSO4室温相的结构为(C66),但其中的Li原子位置并非测定的,而是推断为在三次轴上有较大的空隙处。这一位置与晶体学一般成键理论的认识是有矛眉的,因而最近有人提出了异议。我们重新测定了这一晶体结构,特别是实测了Li原子的位置。新定出的KLiSO4晶体结构中的Li原子位置是:x=1/3,y=2/3,z=0.1797(16)。而Bradley所推断的Li原子位置是:x=1/3,y=2/3,z=0.3488。前者与文献[8]中估算值相接近。新定出的Li原子位置与近邻O原子构成了键长约在1.9A左右的Li—O四面体。
关键词: 相似文献
11.
采用辉光放电技术和等离子体质谱诊断技术,研究了H2/C4H8混合气体等离子体中正离子成分及主要正离子能量随射频功率的变化规律,并分析了H2/C4H8混合气体主要的离解机理和形成过程.研究表明:随着射频功率的增加,碳氢碎片离子的浓度增加,在20 W时达到最大值,25 W后有所减小.当射频功率小于10 W时,H2/C4H8混合气体等离子体中C4H9+相对浓度最大,当功率大于或等于10 W时,C3H3+相对浓度最大.随着射频功率的增大,碳氢碎片离子的能量逐渐增加.对H2/C4H8混合气体等离子体的组成与能量进行的定性分析,将为H2/C4H8混合气体辉光放电聚合物涂层工艺参数优化提供参考. 相似文献
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G.B. Lebron 《Journal of Molecular Spectroscopy》2010,261(2):119-123
The Fourier transform infrared (FTIR) spectrum of the ν3 band of C2H3D was measured at an unapodized resolution of 0.0063 cm−1 in the 1240-1340 cm−1 region. Rovibrational constants for the upper state (ν3 = 1) up to five quartic and two sextic centrifugal distortion terms had been obtained by assigning and fitting a total of 1037 infrared transitions using a Watson’s A-reduced Hamiltonian in the Ir representation. The root-mean-square deviation of the fit was 0.00051 cm−1. The ground state rovibrational constants were also determined by a fit of 674 combination differences together with 21 microwave frequencies from the present infrared measurements with a root-mean-square deviation of 0.00040 cm−1. The upper state (ν3 = 1) and ground state rovibrational constants of C2H3D represent the most accurate values obtained so far. The A-type ν3 band, centred at 1288.788826 ± 0.000044 cm−1 was found to be relatively free from local frequency perturbations. From the ν3 = 1 rovibrational constants obtained, the inertial defect Δ3 was 0.1619724 ± 0.0000001 μÅ2. 相似文献
14.
利用紫外光电子谱(UPS)对乙烯(C2H4)和乙炔(C2H2)气体在Ru(1010)表面的吸附及与K的共吸附进行了研究,实验结果表明:当衬底温度超过200K,乙烯即发生脱氢反应后,σCH和σCC能级均向高结合能方向移动.在室温下,σCH和σCC能级位置与乙炔在Ru(1010)表面的吸附时的分子能级完全一致.乙烯发生脱氢反应后的主要产
关键词:
乙烯
乙炔
钾
Ru(1010)表面 相似文献
15.
The absorption spectrum of the ν6 band of C2H3D centered near 1125.27674 cm−1 in the 1100-1250 cm−1 region was recorded with an unapodized resolution of 0.0063 cm−1 using a Fourier transform infrared (FTIR) spectrometer. A total of 947 infrared transitions of the A-B hybrid-type band were assigned and fitted to upper-state (ν6 = 1) rovibrational constants using a Watson’s A-reduced Hamiltonian in the Ir representation up to eighth-order centrifugal distortion terms. The b-type infrared transitions of the band were analyzed for the first time. The root-mean-square deviation of the fit was 0.00062 cm−1. The ground-state rovibrational constants up to eighth-order terms were also obtained by a fit of 617 combination differences from the present infrared measurements, simultaneously with 21 microwave frequencies with a root-mean-square deviation of 0.00055 cm−1. From this work, the upper-state (ν6 = 1) and ground-state constants of C2H3D were derived with the highest accuracy, so far. The a- and b-type transitions of the hybrid ν6 band were found to be relatively free from local frequency perturbations. The ratio of the a- to b-type vibrational dipole transition moments (μa/μb) was found to be 1.05 ± 0.10. From the ν6 = 1 rovibrational constants obtained, the inertial defect Δ6 was calculated to be 0.3570 ± 0.0008 μÅ2. 相似文献
16.
利用辉光放电技术采用等离子体质谱诊断的方法研究了不同工作 压强下H2/C4H8混合气体等离子体中 主要正离子成分及其能量的变化规律, 并分析了压强对H2/C4H8混合气体的离解机理以及主要正离子形成过程的影响. 结果表明: 随着工作压强的增加, 碳氢碎片离子的浓度和能量均逐渐减小. 当工作压强为5 Pa时, H2/C4H8混合气体等离子体中C3H5+相对浓度最大; 压强为10 Pa时, C3H3+相对浓度最大; 压强为15, 20 Pa时, C2H5+相对浓度最大; 压强为25 Pa时, C4H9+相对浓度最大. 对H2/C4H8等离子体中的主要组分及其能量分布所进行的定性分析, 将为H2/C4H8混合气体辉光放电聚合物涂层的工艺参数优化提供参考技术基础.
关键词:
辉光放电技术
等离子体质谱诊断
工作压强 相似文献
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MRCI study of spectroscopic and molecular properties of X1Σg+ and A1Πu electronic states of the C2 radical 下载免费PDF全文
The potential energy curves (PECs) of X1Σ+g and A1Πu electronic states of the C2 radical have been studied using the full valence complete active space self-consistent field (CASSCF) method followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach in conjunction with the aug-cc-pV6Z basis set for internuclear separations from 0.08 nm to 1.66 nm. With these PECs of the C2 radical,the spectroscopic parameters of three isotopologues ( 12C2 ,12C13C and 13C2 ) have been determined. Compared in detail with previous studies reported in the literature,excellent agreement has been found. The complete vibrational levels G(υ),inertial rotation constants B υ and centrifugal distortion constants D υ for the 12C2 ,12C13C and 13C2 isotopologues have been calculated for the first time for the X1Σ+g and A1Πu electronic states when the rotational quantum number J equals zero. The results are in excellent agreement with previous experimental data in the literature,which shows that the presented molecular constants in this paper are reliable and accurate. 相似文献
19.
A. Chatterji 《Journal of Physics and Chemistry of Solids》2007,68(8):1603-1609
A crystal field (CF) investigation of the magnetic properties of [TbCu6(μ3-OH)3(HL)2(L)4](ClO4)2·25H2O (H2L=imino-diacetic acid) has been carried out. An enhancement of the average magnetic susceptibility (defined by =(χ||+2χ⊥)/3, where χ|| and χ⊥ are the magnetic susceptibilities parallel and perpendicular to the symmetrical axis of the cluster) with respect to the Tb3+ free ion value has been noticed and is attributed to the Tb-Cu interaction. The CF parameters obtained for the system for the first time have been exploited to find the Stark splitting of the 7F manifold of Tb3+, paramagnetic resonance g-values, and the heat capacity. Two anomalies are obtained in the heat capacity at 40 and 5 K; the peak values are 3.1 and 5.98 J mol−1 K−1, respectively. 相似文献
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Marcel Snels Giuseppe D'AmicoEl Bachir Mkadmi 《Journal of Molecular Spectroscopy》2002,216(2):191-196
The infrared spectra of isotopically pure CD235Cl2 have been recorded at a resolution of 0.0026 cm−1 (FWHM) in the range 600-1160 cm−1 with a Bruker IFS 120 HR Fourier transform interferometer. The absorption between 670 and 750 cm−1 is due to three fundamentals, ν3 (weak), ν7 (very weak), and ν9 (strong). A satisfactory analysis of the observed spectra has been obtained by including a c-Coriolis coupling between ν3 and ν9 and a b-Coriolis term between ν7 and ν9. Although no transitions could be observed for the very weak ν7 band, its band origin could be estimated from the Coriolis interaction with ν9. From the analysis of about 4200 assigned transitions of the ν3 and ν9 bands, excited state constants have been determined up to sextic terms. The Coriolis parameters obtained are compared to those calculated from a harmonic force field. 相似文献