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1.
The even-parity autoionizing resonance series 5p5np'[3/2]1, [1/2]1, and 5p5nf'[5/2]3 of xenon have been investigated, excited from the two metastable states 5p56s[3/2]2 and 5p56s'[1/2]0 in the photon energy range of 28000-42000 cm-1 with experimental bandwidth of ~0.1 cm-1. The excitation spectra of the even-parity autoionizing resonance series show typical asymmetric line shapes. New level energies, quantum defects, line profile indices and resonance widths, resonance lifetimes and reduced widths of the autoionizing resonances are derived by a Fano-type line-shape analysis. The line profile index and the resonance width are shown to be approximately proportional to the effective principal quantum number. The line separation of the 5p5np' autoionizing resonances is discussed.  相似文献   

2.
The even-parity autoionizing resonance series 4p5np′[3/2]1,2,[1/2]1,and 4p5nf′[5/2]3of krytpon have been investigated by laser excitation from the two metastable states 4p55s[3/2]2and 4p55s′[1/2]0in the photon energy region of 29000–40000 cm 1at experimental bandwidth of~0.1 cm 1.The excitation spectra of the even-parity autoionizing resonance series,most of which are experimentally studied for the first time in this work,show typical asymmetric line shapes.Complementary information on level energies,quantum defects,line profile indices and resonance widths,resonance lifetimes and reduced widths of the autoionizing resonances are derived by Fano-type line-shape analyses of the experimental results.Results from this work indicate that the line profile index(q)and the resonance width()are approximately proportional to the effective principal quantum number(n*);the line separation of the 4p5np′autoionizing resonances is also in good agreement with theoretical model.  相似文献   

3.
Kr atoms were produced in their metastable states 4p55s [3/2]2 and 4p55s’ [1/2]0 in a pulsed DC discharge in a beam, and subsequently excited to the even-parity autoionizing Rydberg states 4p5 np′ [3/2]1,2, [1/2]1 and 4p5 nf′ [5/2]3 using single photon excitation. The excitation spectra of the even-parity autoionizing resonance series from the metastable Kr were obtained by recording the autoionized Kr+ ions with time-of-flight ion detection in the photon energy range of 29000–40000 cm−1. A wealth of autoionizing resonances were newly observed, from which more precise and more systematic spectroscopic data of the level energy and quantum defects were derived. Supported by the National Natural Science Foundation of China (Grant No. 20673107), the National Key Basic Research Special Foundation of China (Grant No. 2007CB815203), and Chinese Academy of Sciences (Grant No. KJCX2-SW-H08)  相似文献   

4.
Metastable 40Ar* atoms are produced in the two metastable states 3p54s[3/2]2 and 3p54s′[1/2]0 in a pulsed DC discharge in a beam, and are subsequently excited to the even-parity autoionizing resonance series 3p5np′ [3/2]1,2, 3p5np′ [1/2]1, and 3p5nf′ [5/2]3 using single photon excitation with a pulsed dye laser. The excitation spectra of the even-parity autoion-izing resonance series from the metastable 40Ar* are obtained by recording the autoionized Ar+ ions with time-of-flight ion detection in the photon energy range of 32500-35600 cm-1 with an experimental bandwidth of <0.1 cm-1. A wealth of autoionizing resonances are newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects are derived.  相似文献   

5.
在单光子29000~40000cm^-1。能量范围内,获得亚稳态4p55s[3/2]2和4p^5s’[1/2]oKr原子向其4p5npr[3/2]1.2,[1/2]1和4p5nfr[5/2]3序列自电离Rydberg态跃迁的共振增强激发光谱,光谱线宽≈0.1cm^-1.这些偶宇称自电离态的激发谱呈现明显的不对称线形,如此高分辨的激发谱大部分是首次报道.根据Fano线形关系对激发谱进行系统地分析,获得许多新的系统的能级位置、量子亏损、线性因子、共振宽度、共振态寿命和衰减宽度等数据,基于实验拟合所得的系统参数,我们发现线形因子和共振宽度相对有效量子数呈线性关系.另外还分析了4p^5np'序列的能级间距.  相似文献   

6.
Summary. 2 [Yb2(NH2)2(Pz)4][Yb(NH3)2(Pz)3 PzH], Pz = pyrazolate anion, PzH = pyrazole, C3H4N2 is obtained by the reaction of ytterbium metal with pyrazole in liquid ammonia and subsequent increase of the temperature to 200°C resulting in the formation of colorless single crystals of the compound. The X-ray single crystal analysis reveals that the structure consists of 2 [Yb2(NH2)2(Pz)4] planes with neutral [Yb(NH3)2(Pz)3 PzH] monomeric molecules that are located between the planes and ytterbium is trivalent. This is the first example of a two-dimensional network structure of an organic amine of the rare earth elements that derives from an electride induced synthesis. The product decomposes under release of ammonia outside its sealed reaction vessel, viz. if the NH3 pressure is removed.  相似文献   

7.
2 [Yb2(NH2)2(Pz)4][Yb(NH3)2(Pz)3 PzH], Pz = pyrazolate anion, PzH = pyrazole, C3H4N2 is obtained by the reaction of ytterbium metal with pyrazole in liquid ammonia and subsequent increase of the temperature to 200°C resulting in the formation of colorless single crystals of the compound. The X-ray single crystal analysis reveals that the structure consists of 2 [Yb2(NH2)2(Pz)4] planes with neutral [Yb(NH3)2(Pz)3 PzH] monomeric molecules that are located between the planes and ytterbium is trivalent. This is the first example of a two-dimensional network structure of an organic amine of the rare earth elements that derives from an electride induced synthesis. The product decomposes under release of ammonia outside its sealed reaction vessel, viz. if the NH3 pressure is removed.  相似文献   

8.
The complex dicarbonylbis(diphenylethylphosphine)platinum, Pt(CO)2[P(C6H5)2(C2H5)]2, crystallizes in either of the enantiomorphous space groups P3121 (No. 152) and P3221 (No. 154) with cell dimensions a = 10.64(1), c = 22.06(1) Å, U = 2163 Å3; pc = 1.564 g/cm3 for Z = 3, pm = 1.55(3) g/cm3. The intensities of 1177 independent reflections have been determined by counter methods with MoKα monochromatized radiation. The structure has been solved by the heavy atom method. The refinement, carried out by full-matrix least squares down to a final R factor of 0.042, has enabled the absolute configuration of the crystal sample (space group P3121) to be ascertained. The molecule is roughly tetrahedral, and has the metal atom lying on a two-fold axis of the cell. Bond parameters are: PtC = 1.92(2) Å, PtP = 2.360(4) Å, CPtC = 117(1)° and PPtP = 97.9(2)°. The PtC2 and PtP2 moieties make a dihedral angle of 86.0(3)°. The overall C2 symmetry of the molecule is probably only a statistically averaged situation, a disorder in the PtCO interactions being apparent from the orientations of the thermal ellipsoids of the C and O atoms.  相似文献   

9.
Crystals of the rhenium cluster complex (H3O)4[(C2H5)4N]6[Th2Cl4(H2O)12O]3[Re4Se4(CN)12]4 are obtained in an acidic (HCl) aqueous solution by the reaction of cluster salt K4[Re4Se4(CN)12]·6H2O with ThCl4 and (C2H5)4NCl. Single crystal X-ray analysis shows that the title compound is ionic and crystallizes in the cubic crystal system (a = 22.7322(3) ?, V = 11746.93(27) ?3, Z = 2, I4 3m space group, R = 0.0350). It contains [Th2Cl4(H2O)12O]2+ cations with two thorium atoms bonded to each other through the bridging oxygen atom forming an angle of 180° in the structure.  相似文献   

10.
Reaction between Mo(CO)6 and p-C5NH4SO3Na (1:2 (Mo: p-C5NH4SO3Na) stoichiometric ratio) gave the trans-Mo(CO)4(p-C5NH4SO3Na)2 complex, (1), in 80% yield. Complex (1) has been characterized by FTIR, 1H and 13C NMR spectroscopy. Complex (1) has most likely an idealized D4h geometry with trans N-bound p-C5NH4SO3Na ligands.  相似文献   

11.
By measuring the relative CO quantum yields from ketene photolysis as a function of photolysis wavelength we have determined the threshold energy at 25° for CH2CO(1A1) → CH2(3B1) + CO(1Σ+) to be 75.7 ± 1.0 kcal/mole. This corresponds to a value of 90.7 ± 1.0 kcal/mole for ΔHf2980[CH2(3B1)]. By measuring the relative ratio of CH2(1A1)/CH2(3B1) from ketene photolysis as a function of photolysis wavelength we have determined the threshold energy at 25°C for CH2CO(1A1) → CH2(1A1) + CO(1Σ+) to be 84.0 ± 0.6 kcal/mole. This corresponds to a value of 99.0 ± 0.6 kcal/mole for ΔHf2980[CH2(1A1)]. Thus a value for the CH2(3B1) ? CH2(1A1) energy splitting of 8.3 ± 1 kcal/mole is determined, which agrees with three other recent independent experimental estimates and the most recent quantum theoretical calculations.  相似文献   

12.
Double complex salts (DCSs) [Co(NH3)6][Fe(CN)6] (I) and [Co(NH3)6]2[Cu(C2O4)2]3 (II) and complex [Co(NH3)6]2(C2O4)3·4H2O (III) are synthesized and investigated by single crystal XRD, crystal optics, and elemental analysis. The crystalline phases of I, II, and III (R-3, P21/c, and Pnnm space groups respectively) have the following crystallographic characteristics: a = 10.9804(2) ?, b = 10.9804(2) ?, c = 10.8224(3) ?, V = 1130.03(4) ?3, Z = 3, d x = 1.65 g/cm3 (I); a = 9.6370(2) ?, b = 10.2452(2) ?, c = 13.2108(3) ?, V = 1932.90(9) ?3, Z = 2, d x= 1.97 g/cm3 (II), and a = 11.7658(3) ?, b = 11.7254(3) ?, c = 14.1913(4) ?, V = 1304.34(5) ?3, Z = 2, d x = 1.68 g/cm3 (III). This paper investigates the products of DCS thermolysis in a hydrogen atmosphere: the intermetallic compound CoFe with the bcc parameter a = 2.852 ? for I and a heterogeneous mixture of Co and Cu in the decomposition of II. The coordinated CN and C2O42− groups then turn into NH3, hydrocarbons, and CO2. The dominant hydrocarbon is methane.  相似文献   

13.
Vibrationally resolved partial photoionization cross sections of O2 leading to the b4Σ?g and B2Σ?1g(3σ?1g) tonic states have been measured at high resolution in a wide photon energy range from 0.5 eV above threshold to 24.5 eV. The σu shape resonance is observed around 21.5 eV, in fairly good agreement with “one-electron” theoretical predictions. The series of resonances from 19 to 20 5 eV result from an autoionization process with a strong vibrational selectivity, explained by the similar geometries of the resonance states and the b ionic state. The large resonance widths originate from a strong Rydberg-valence orbital mixing Calculations using multichannel quantum defect theory reproduce the most important features.  相似文献   

14.
Xenon atoms were produced in their metastable states 5p56s3/22 and 5p56s′1/20 in a pulsed DC discharge in beam,and subsequently excited to the even-parity autoionizing Rydberg states 5p5np′3/21,1/21,and 5p5nf′ 5/23 using single photon excitation. The excitation spectra of the even-parity autoionizing resonance series from the metastable 129Xe were obtained by recording the autoionized Xe+ with time-of-flight ion detection in the photon energy range of 28000-42000cm-1 .A wealth of autoionizing resonances were newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects were derived.  相似文献   

15.
The properties of the autoionizing 3p 511s’ [1/2]1 Argon I level have been experimentally studied in the presence of a strong magnetic field (2.14-2.22 T). Quasi- Landau type oscillations have been observed in the width and position of the 3p 5-4p[1/2]0 -3p 511s’ [1/2]1 exciting transition. The results provide an additional support for earlier observations of Lemoigne et al. [7]. No evidence for similar oscillations in magnetic field dependence of the Fano q parameter was observed.  相似文献   

16.
The solid-state reactions of UO3 and WO3 with M2CO3 (M=Na, K, Rb) at 650°C for 5 days result, accordingly the starting stoichiometry, in the formation of M2(UO2)(W2O8) (M=Na (1), K (2)), M2(UO2)2(WO5)O (M=K (3), Rb (4)), and Na10(UO2)8(W5O20)O8 (5). The crystal structures of compounds 2, 3, 4, and 5 have been determined by single-crystal X-ray diffraction using Mo(Kα) radiation and a charge-coupled device detector. The crystal structures were solved by direct methods and Fourier difference techniques, and refined by a least-squares method on the basis of F2 for all unique reflections. For (1), unit-cell parameters were determined from powder X-ray diffraction data. Crystallographic data: 1, monoclinic, a=12.736(4) Å, b=7.531(3) Å, c=8.493(3) Å, β=93.96(2)°, ρcal=6.62(2) g/cm3, ρmes=6.64(1) g/cm3, Z=4; 2, orthorhombic, space group Pmcn, a=7.5884(16) Å, b=8.6157(18) Å, c=13.946(3) Å, ρcal=6.15(2) g/cm3, ρmes=6.22(1) g/cm3, Z=8, R1=0.029 for 80 parameters with 1069 independent reflections; 3, monoclinic, space group P21/n, a=8.083(4) Å, b=28.724(5) Å, c=9.012(4) Å, β=102.14(1)°, ρcal=5.83(2) g/cm3, ρmes=5.90(2) g/cm3, Z=8, R1=0.037 for 171 parameters with 1471 reflections; 4, monoclinic, space group P21/n, a=8.234(1) Å, b=28.740(3) Å, c=9.378(1) Å, β=104.59(1)°, ρcal=6.13(2) g/cm3,  g/cm3, Z=8, R1=0.037 for 171 parameters with 1452 reflections; 5, monoclinic, space group C2/c, a=24.359(5) Å, b=23.506(5) Å, c=6.8068(14) Å, β=94.85(3)°, ρcal=6.42(2) g/cm3,  g/cm3, Z=8, R1=0.036 for 306 parameters with 5190 independent reflections. The crystal structure of 2 contains linear one-dimensional chains formed from edge-sharing UO7 pentagonal bipyramids connected by two octahedra wide (W2O8) ribbons formed from two edge-sharing WO6 octahedra connected together by corners. This arrangement leads to [UW2O10]2− corrugated layers parallel to (001). Owing to the unit-cell parameters, compound 1 probably contains similar sheets parallel to (100). Compounds 3 and 4 are isostructural and the structure consists of bi-dimensional networks built from the edge- and corner-sharing UO7 pentagonal bipyramids. This arrangement creates square sites occupied by W atoms, a fifth oxygen atom completes the coordination of W atoms to form WO5 distorted square pyramids. The interspaces between the resulting [U2WO10]2− layers parallel to plane are occupied by K or Rb atoms. The crystal structure of compound 5 is particularly original. It is based upon layers formed from UO7 pentagonal bipyramids and two edge-shared octahedra units, W2O10, by the sharing of edges and corners. Two successive layers stacked along the [100] direction are pillared by WO4 tetrahedra resulting in sheets of double layers. The sheets are separated by Na+ ions. The other Na+ ions occupy the rectangular tunnels created within the sheets. In fact complex anions W5O2010− are built by the sharing of the four corners of a WO4 tetrahedron with two W2O10 dimmers, so, the formula of compound 5 can be written Na10(UO2)8(W5O20)O8.  相似文献   

17.
Phase diagrams on the mole fraction scale are presented for decane- (R4N)2[Nd(NO3)5]-n-octanol(n-butanol, n-decanol) (1–2–3) ternary liquid systems, where R4N+ stands for trialkylbenzylammonium, at T = 298.15 K. The C10H22-(R4N)2[Nd(NO3)5] binary system is a two-phase liquid system. One phase (phase I) is the almost neat solvent; the other (phase II) is enriched in (R4N)2[Nd(NO3)5]. The liquid ternary systems are characterized by homogeneous and two-phase liquid solution fields. One phase is enriched in (R4N)2[Nd(NO3)5] and n-octanol (n-butanol, n-decanol) and the other in C10H22. The miscibilities in the C10H22-(R4N)2[Nd(NO3)5] binary system and in the ternary liquid systems were used to calculate, from the equations of the nonrandom two-liquid model (NTRL), intermolecular interaction parameters and excess Gibbs free energies g E for the binary and ternary liquid systems along the binodal curve. g E > 0 is characteristic of the systems under study, while g E decreases in the series of pairs of liquids (1, 2), (1, 3), and (2, 3) Original Russian Text ? A.K. Pyartman, V.A. Keskinov, P.V. Zaitsev, N.A. Charykov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1392–1397.  相似文献   

18.
Two new Fischer-type carbene-containing trinuclear transition-metal clusters: (μ 3-S)Co3(CO)7[μ, η 2-SCNEt2] 1 and CoRu2(CO)9[μ 3, η 2-SCNEt2] 2 were obtained by the reaction of tris(N,N-diethyldithiocarbamato)cobalt with Co2(CO)8 and Ru3(CO)12. These clusters contain thiocarboxamido ligand in different coordination modes. The thiocarboxamido ligand served as monometalated or dimetalated sulfur(diethy1amino) carbene ligand in these clusters. Clusters 1 and 2 were characterized by IR, 1H NMR, and single-crystal X-ray diffraction.  相似文献   

19.
Single crystals of (CN3H6)2[(UO2)2(C2O4)(SeO3)2] were synthesized and studied by IR spectroscopy and X-ray diffraction. The compound crystallizes in the triclinic system with the unit cell parameters a = 7.1169(12) ?, b = 7.4874(10) ?, c = 8.9748(14) ?, α = 88.243(6)°, β = 74.546(6)°, γ = 81.445(6)°, space group P[`1]P\bar 1, Z = 1, R = 0.0304. The main structural units of the crystals are layers of the [(UO2)2(C2O4)(SeO3)2]2− composition; the layers belong to the crystal chemical group A 2 K 02 T 23 (A = UO22+ K 02 = C2O42−, T 3 = SeO3) of uranyl complexes. Uranium-containing complex groups are linked by electrostatic interactions and a network of hydrogen bonds with CN3H6+ guanidinium ions to form a three-dimensional framework.  相似文献   

20.
The Screening Constant by Unit Nuclear Charge (SCUNC) method is used to study (2pns) 1,3P° and (2pnd) 1,3P° autoionizing states of the beryllium atom. Energy positions are reported up to n=20. In addition, resonance widths of the (2pns) 1P° states also presented. The current results compared very well to available theoretical and experimental literature values up to n=15. The accurate data presented in this work may be of interest for future experimental and theoretical studies in the photoabsorption spectrum of Be.  相似文献   

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