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1.
Using laser flash photolysis/transient absorption technique for the study of two photon photodissociation of carbon disulfide in acetonitrile solution at 266 nm, the transient UV-Vis absorption spectrum of Rydberg state CS2 (6sσg) within 240-370 nm and subsequent dissociation product CS (α^3П) with the maximum absorption at 260 nm were directly observed. The lifetime of CS (α^3П) in the nitrogen and oxygen saturated solution is also studied in our experiment. 相似文献
2.
Abstract Neptunium and plutonium monosulfides were studied under high pressure up to ~60 GPa using a diamond anvil cell in an energy dispersive X-ray diffraction facility. The compounds, of cubic rock salt structure type at ambient pressure, do not show any crystallographic phase transition in the domain of investigation. From the pressure-volume relationship, we determined bulk moduli of 92 and 120 GPa with pressure derivatives of 4.6 and 4.1 for NpS and PUS respectively. 相似文献
3.
Ab initio MRCI+Q study on potential energy curves and spectroscopic parameters of low-lying electronic states of CS+
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Carbon monosulfide molecular ion (CS+), which plays an important role in various research fields, has long been attracting much interest. Because of the unstable and transient nature of CS+, its electronic states have not been well investigated. In this paper, the electronic states of CS+ are studied by employing the internally contracted multireference configuration interaction method, and taking into account relativistic effects (scalar plus spin–orbit coupling). The spin–orbit coupling effects are considered via the state-interacting method with the full Breit–Pauli Hamiltonian. The potential energy curves of 18 Λ–S states correlated with the two lowest dissociation limits of CS+ molecular ion are calculated, and those of 10 lowest Ω states generated from the 6 lowest Λ–S states are also worked out. The spectroscopic constants of the bound states are evaluated, and they are in good agreement with available experimental results and theoretical values. With the aid of analysis of Λ–S composition of Ω states at different bond lengths, the avoided crossing phenomena in the electronic states of CS+ are illuminated. Finally, the single ionization spectra of CS (X1Σ+) populating the CS+(X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+) states are simulated. The vertical ionization potentials for X2Σ1/2+, A2Π3/2, A2Π1/2, and B2Σ1/2+ states are calculated to be 11.257, 12.787, 12.827, and 15.860 eV, respectively, which are accurate compared with previous experimental results, within an error margin of 0.08 eV~0.2 eV. 相似文献
4.
Huang MD Becker-Ross H Florek S Heitmann U Okruss M Patz CD 《Analytical and bioanalytical chemistry》2008,390(1):361-367
A new method for the determination of sulfur forms in wine, i.e., free SO2, total SO2, bound SO2, total S, and sulfate, is presented. The method is based on the measurement of the carbon monosulfide (CS) molecular absorption
produced in a conventional air–acetylene flame using high-resolution continuum source absorption spectrometry. Individual
sulfur forms can be distinguished because of the different sensitivities of the corresponding CS molecular absorption. The
sensitivity of free SO2 is about three times higher than the value for bound SO2 and sulfate. The method makes use of procedures similar to those used in classic reference methods. Its performance is verified
by analyzing six wine samples. Relative standard deviations are between 5 and 13% for free SO2 and between 1 and 3% for total SO2. For the validation of the accuracy of the new method, the results are compared with those of reference methods. The agreement
of the values for total SO2 with values of the classic method is satisfactory: five out of six samples show deviations less than 16%. Due to the instability
of free SO2 in wine and the known problems of the used reference method, serious deviations of the free SO2 results are found for three samples. The evaluation of the limits of detection focuses on the value for free SO2, which is the sulfur form having by far the lowest concentration in wine. Here, the achievable limit of detection is 1.8 mg L−1.
Figure Detection of non-metal elements using continuum source flame absorption spectrometry 相似文献
5.
Two mixtures of pentlandite and the monosulfide solid solution (mss) have been synthesized. The bulk compositions of the samples
are Fe6Ni3S8 and Fe3Ni6S8. Differential scanning calorimetry detected exothermic process in the samples under heating. The process takes place in temperature
range between phase transition in the mss (near 400 K) and 690 K and is governed by diffusion.
X-ray powder diffraction has showed that equilibrium Fe-Ni distribution between pentlandite and the mss is achieved after
short-time heating up to 670 K.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
合成出了一硫化四甲基秋兰姆(TMTM),采用溶剂蒸发法培养出了单晶TMTM,通过XRD单晶衍射仪、FTIR、TG-DSC对其进行检测和表征,揭示了单晶TMTM的微观结构和内在规律性。XRD单晶衍射从衍射数据、部分健长和键角, 揭示TMTM的微观结构,单晶TMTM高度有序化的定向排列结构,决定了其高效的橡胶硫化促进性能。TG-DSC从热效应分析TMTM的性质,FTIR、TG-DSC检测结果表明,单晶TMTM中蕴含很少许的二硫化碳,FTIR揭示了TMTM内部的化学键键型,和单晶衍射仪从不同侧面检测的结果一致,为确定TMTM的分子结构提供了实验依据。TMTM的分解温度偏高,为采用硫化仪研究TMTM的橡胶硫化性能提供参考。本研究为企业选定工作标准品,对TMTM工业化生产进行跟踪检测,评判TMTM的产品性能指标,填报立项TMTM化工行业标准的申报,撰写标准草案,完成国家工业和信息化部的标准制修订项目计划,提供基础实验数据。 相似文献
7.
《Journal of Coordination Chemistry》2012,65(1-2):91-99
Abstract Fenske-Hall molecular orbital calculations on the complexes CpFe(CO)2(CX)+ (X = O, S, Se, and Te) have been used to quantify the nature of bonding between the CX ligands and the metal atom. In addition, conclusions have been reached about the reactivity of the complexes under both nucleophilic and electrophilic attack. The previously established trend of increasing metal—ligand bond strength as X changes from O to S to Se is demonstrated by our molecular orbital calculations, and found to extend to Te. The mechanism for nucleophilic attack, variously explained in the past by either charge control or orbital control, is quantitatively ascribed to orbital control only. The nature of electrophilic attack on these complexes is also found to begin with orbital control. 相似文献
8.
Emission spectra of the A2Π3/2-X2Σ+ (0, 1), (0, 0), and (1, 0) bands and the B2Σ+-X2Σ+ (0, 1), (0, 0), (1, 0), (2, 0), and (3, 1) bands of ScS have been recorded in the 10 000-13 500 cm−1 region at a resolution of 0.05 cm−1 using a Fourier transform (FT) spectrometer. The A2Πr-X2Σ+ (1, 0) band as well as the B2Σ+-X2Σ+ (0, 0) and (1, 0) bands have been recorded at high resolution (±0.001 cm−1) by laser excitation spectroscopy using a supersonic molecular beam source. The FT spectral features range up to N = 148, while those recorded with the laser cover the “low-N” regions. The lines recorded with the laser exhibit splittings due to the 45Sc (I = 7/2) magnetic hyperfine interactions, which are large (∼6.65 GHz) in the X2Σ+ state and much smaller in the B2Σ+ and A2Π states. The energy levels were modeled using a traditional ‘effective’ Hamiltonian approach, and improved spectroscopic constants were extracted and compared with previous determinations and theoretical predictions. 相似文献
9.
Syntheses and Characterization of P4O7S P4O7S was synthesized for the first time and characterized by X-ray structure determination (single-crystal methods) and 31P-n.m.r. (solution and MAS-solid) (P1 ; a = 687.2(1); b = 718.2(1); c = 809.1(1) pm; α = 92.58(1)°; β = 104.43(1)°; γ = 94.82(2)°; 2 907 diffractometer data; R1 = 0.030; wR2 = 0.102). The different influences of terminally bound oxygen and sulfur on the geometry of the P4O6 cage are discussed. 相似文献
10.
Using a newly constructed source, tin monosulfide is produced by the reaction between carbonyl sulfide and the products resulting from the ablation of tin metal by the pulsed output of a frequency-doubled Nd:YAG laser (λ = 532 nm). Entrained in argon carrier gas, SnS is introduced into the cavity of a Balle-Flygare Fourier transform microwave spectrometer that has a frequency range encompassing the two lowest rotational transitions (J = 1 − 0 and 2 − 1) for this molecule. Except for 115Sn34S, spectra are obtained in natural abundance for all 34S-containing isotopologues with naturally occurring tin isotopes. Additionally, spectra were obtained for the rare isotopologues, 115Sn32S and 120Sn33S. Resolution of the hyperfine structure in the latter species allows a more precise determination of its 33S nuclear quadrupole coupling constant. Spectra for all species containing 34S are analyzed in terms of mass-independent Dunham parameters and are combined with all available isotopologues to determine Born-Oppenheimer breakdown terms for both tin and sulfur. 相似文献