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1.
The high-resolution Fourier transform infrared spectrum of phosphorus trifluoride PF3 have been reinvestigated in the ν4 perpendicular band region around 347 cm−1. Thanks to recent pure rotational measurements, 595 new infrared transitions of the ν4 band have been assigned extending the rotational quantum number values up to Kmax = 66 and Jmax = 67. As a consequence of this extension, a sophisticated model containing a large number of parameters and interaction constants was adopted for the analysis of the IR transitions of the ν4 fundamental band of PF3. A merge of the IR transitions and the reported MW/MM/RF data within the v4 = 1 excited level yielded an accurate rotational ground state C0 value, 0.159970436 (69) cm−1, which was used to determine an improved GS structure, r0(P-F) = 1.56324405 (11) Å and ?(FPF) = 97.752232 (29)°. All experimental data have been refined applying various reduction forms of the effective rovibrational Hamiltonian developed for an isolated degenerate state of a symmetric top molecule. The v4 = 1 excited state of the PF3 oblate molecule was treated with models taking into account ?- and k-type intravibrational resonances. Parameters up to sixth order have been accurately determined and the unitary equivalence of the derived parameter sets in different reductions was demonstrated.  相似文献   

2.
The extended stretch-bender Hamiltonian, incorporating spin-orbit coupling and overall rotation, has been used to calculate the spin-vibronic structure of the rovibronic energies in the region where the vibronic states of the excited Ã2A1 electronic state of NH2 interact with near-resonant high-lying levels of the X?2B1 state of NH2. A detailed comparison has been made with the experimental measurements which were made of these rovibronic states, the majority of which are due to Ramsay, Vervloet, and their collaborators. We have shown that, as in our study of the vibronic levels of the X?2B1 state below the barrier to linearity, in order to fit the variation of the effective vibronic spin-orbit coupling constant over the whole of this energy regime, the effective linear molecule spin-orbit coupling constant, ASO must be increased from the earlier value of 50 cm−1 of Ch. Jungen, K.-E. J. Hallin, and A. Merer (Mol. Phys.40, 65-94 (1980)) to 61.6 cm−1. The impact of Fermi resonance, in both the Ã2A1 and X?2B1 states, on the observed rovibronic structure has been assessed. The pattern of calculated spin-rovibronic levels, including the effects of spin uncoupling, is in good agreement with that measured experimentally.  相似文献   

3.
Vibration-rotation transitions of diacetylene between the first excited states of the ν6 (CCH symmetric bending) and the ν8 (CCH antisymmetric bending) vibrations were observed with a Stark modulation microwave spectrometer. The rotational, centrifugal distortion and l-type doubling constants of the two vibrational states were determined as follows with 2.5 σ uncertainties in parentheses.
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4.
Kinetics of the apparent isothermal and the non-isothermal crystallization of α-Fe phase within the amorphous Fe81B13Si4C2 alloy were investigated by an X-ray diffraction (XRD) and by a differential scanning calorimetry (DSC). It was established that the apparent isothermal crystallization of α-Fe phase within amorphous Fe81B13Si4C2 alloy could be described by the Johnson-Mehl-Avrami (JMA) kinetic model (with parameter niso=4.0). The apparent isothermal crystallization process includes a constant rate of nucleation and three-dimensional growth of nuclei. The results of X-ray diffraction (XRD) data of the isothermally crystallized samples confirmed the above established kinetic model. From the kinetic analysis of the non-isothermal crystallization of the α-Fe phase within this amorphous alloy, it was concluded that the autocatalytic two-parameter Šesták-Berggren (SB) reaction model (with kinetic exponents M=0.72 and N=1.02) describes well the studied process under the given conditions. The non-isothermal crystallization process involves the constant nucleation rate of stable nuclei with additional secondary two-dimensional (surface) nucleation and overlapping of the growing nuclei on account of the non-isothermal activation.  相似文献   

5.
Infrared spectrum of the cobalt carbonyl radical CoCO produced by the 193 nm excimer laser photolysis of cobalt tricarbonyl nitrosyl Co(CO)3NO was observed by time-resolved diode laser spectroscopy. More than 600 lines were identified as belonging to the ν1 (C-O stretch) fundamental band, consisting of the Ω=5/2 and 3/2 subbands, and the associated hot bands , , , and . The 2Δi electronic ground state of CoCO was experimentally confirmed. The ν1 band origins are 1974.172582(93) cm−1 and 1973.53178(14) cm−1 for the Ω=5/2 and 3/2 subbands, respectively. The rotational constant in the ground state was determined as B0=4427.146(50) MHz. The centrifugal distortion constant D0=1.1243(68) kHz was obtained for the Ω=5/2 substate of the ground state. The equilibrium rotational constant Be=4435.44(14) MHz was derived, together with the vibration-rotation interaction constants.  相似文献   

6.
The rovibrational spectrum of 2ν9 band of CD3CCH is overlapped by two prominent hot bands identified as (2ν90+ν10±1)(E)←ν10±1(E) and 3ν9±1(E)←ν9±1(E), where ν10 and ν9 are the degenerate CCC and CCH bending fundamental vibrations, respectively. Assignment of lines to the transitions of these hot bands were carried out with the help of the high-resolution spectra recorded at ∼195 K and at room temperature. Molecular parameters for these hot bands have been obtained from the rotational analysis of the partially resolved K-structure lines. Only Q-head of the third hot band , originating from the lower 2ν10 state could be identified.  相似文献   

7.
Strongly damped reactions of 238U+238U, at Ecm= 680—1880 MeV have been studied based on the improved quantum molecular dynamics model. We find that at a certain energy region the entrance channel potential is weakly repulsive and the dissipation is very strong after touching configuration, these two effects make the time delay of re-separation for colliding system. The single particle potential well of the transiently formed composite system has Coulomb barrier about 15—20 MeV high at the surface, which makes the excited unbound protons being still embedded in the potential well and moving in a common mono-single particle potential for a period of time and thus restrains from quick decay of the composite system.  相似文献   

8.
In this paper the nuclear structure of hypernucleus 5ΛHe and its effect on the binding energy BΛ of A hyperon are systematically studied. The Polarization effect of the core a is explored. The binding energy BΛ of 5ΛHe including D-state mixing component is calculated. The results show that the core α suffers a serious distortion by the interaction with Λ hyperon and has no longer the structure of a free Alpha Particle. The D-state mixing can improve the BΛ calculated value about 0.5MeV. A Possible three cluster structure is further explored. The Λ+d+d model can give a BΛ value close to the experimental one. The further exploration is necessary.  相似文献   

9.
The ν1 fundamental band of the ClO2 radical has been studied by means of the 10.6-μm CO2 and N2O laser Stark spectroscopy. More than 250 and 150 Stark resonances were assigned for the 35ClO2 and 37ClO2 species, respectively, and were analyzed together with the recent microwave and laser-microwave double resonance results to give molecular constants including spin-rotation interaction constants. The ν1 band origins and electric dipole moments both in the ground and ν1 states were determined accurately
Bv (MHz)Dv (kHz)qv (MHz)
ν64391.3230(84)0.582(154)2.4830(32)
ν84391.1921(94)0.594(179)2.4073(37)
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10.
An investigation of the torsion-rotation-vibration energies in the ν5 vibrational state in CH3CF3 has been carried out using infrared and mm-wave spectroscopy. The lowest frequency parallel fundamental band ν5 near 600 cm−1 has been measured at a resolution of 0.00125 cm−1 with Fourier transform spectroscopy for the two lowest torsional states v6=0 and 1. The cold band (v5=1, v6=0)←(v5=0, v6=0) showed no torsional splittings and looked much like a parallel band in a C3v molecule. The hot band (v5=1, v6=1)←(v5=0, v6=1) consisted of three distinct subbands, one for each torsional sublevel σ=0, +1, and −1. For the state (v5=1, v6=1), the torsional splitting was increased from ∼0.001 cm−1 to ∼0.022 cm−1 by torsion-mediated Fermi-type interaction primarily with the dark state (v5=0, v6=5). The effects of this coupling on the spectrum are striking in spite of the fact that the two interacting states are ∼100 cm−1 apart and differ by four units in v6. The large amplitude character of the state (v5=0, v6=5) is seen to be largely responsible for the unusual (k, σ) dependence of the energies in the state (v5=1, v6=1). The pure rotational spectrum in the state (v5=1, v6=0) has been measured between ∼50 and 370 GHz with Doppler-limited resolution; no σ-splitting was detected. The 3590 infrared and mm-wave frequencies measured here have been analyzed together with the 1494 measurements reported earlier by Wang et al. in an analysis of the vibrational ground state (2001, J. Mol. Spectrosc.205, 146-163). A good fit was obtained here by varying 36 parameters in a Hamiltonian which takes into account the interaction between the torsional stacks of levels for v5=0 and 1, as well as the (A1A2) splittings measured earlier for v5=0. The explicit treatment of the interstack interactions is shown to lead to significant changes in the parameters (V0,3, V0,6) that characterize the torsional potential for v5=0. These changes have been explained quantitatively by examining the contact transformation that is implicitly applied when the interstack coupling is neglected.  相似文献   

11.
Capabilities of the method of laser null ellipsometry for the study of optical parameters of thin films of multicomponent alloys are demonstrated. Films of alloys (HfO2) x (Al2O3)1 − x on single-crystal silicon are obtained by the chemical vapor deposition with the use of the following volatile compounds: hafnium dipivaloylmethanate (IV) and aluminum acetylacetonate (III). The selection of initial sets for their optical parameters is justified. The selected model is shown to correspond to experimental data. In films deposited from the mixture of precursors, the refractive index increases from a substrate to a film surface. Due to the separation of sources, films described by a single-layer model were deposited. This fact is indicative of the homogeneous distribution of components over the film thickness.  相似文献   

12.
The spectrum of the ν7 band of cis-ethylene-d2 (cis-C2H2D2) has been recorded with an unapodized resolution of 0.0063 cm−1 in the 740-950 cm−1 region using a Bruker IFS 125 HR Fourier transform infrared spectrometer. By fitting 2186 infrared transitions of ν7 with a standard deviation of 0.00060 cm−1 using a Watson’s A-reduced Hamiltonian in the Ir representation, accurate rovibrational constants for ν7 = 1 state have been derived. The band center of ν7 has been found to be 842.20957 ± 0.00004 cm−1. In a simultaneous fit of 1331 infrared ground state combination differences from the present ν7 transitions, together with 22 microwave frequencies, ground state constants have been improved. The rms deviation of the ground state fit was 0.00027 cm−1.  相似文献   

13.
The asymmetric stretching fundamental of the PO2 free radical in its ground electronic state has been measured between 1280 and 1360 cm−1 using diode laser absorption spectroscopy. This new data set has been combined in a fit with an earlier, smaller infrared data set and with pure rotational transitions measured by microwave and laser magnetic resonance spectroscopies to provide a new set of parameters for the ground and ν3 = 1 states of A1 PO2. These parameters can be used to calculate line positions in this band for transitions up to N = 50.  相似文献   

14.
张玉美  许甫荣 《中国物理 C》2008,32(Z2):150-151
We have employed the shell model and Skyrme-Hartree-Fock methods to investigate the structure of the neutron-rich nucleus 19N. The level scheme of 19N from the shell-model calculation with the WBT interaction is displayed. The potential-energy-surface calculation with the SGII interaction implies that 19N should be a deformed nucleus. The theoretical β-decay half life of 19N reproduces well the available experimental data.  相似文献   

15.
The electronic and the magnetic properties of the molecule-based magnet [Co(μ1,3-SCN)2(μ1,6-dmpzdo)]n (where dmpzdo=2,5-dimethylpyrazine-1,4-dioxide) have been investigated using first-principles, namely density-functional theory (DFT) with the generalized gradient approximation (GGA) method and the full-potential linearized augmented plane-wave method (FP_LAPW). The total energy, the spin magnetic moments and the density of states (DOSs) were all calculated and spin distributions in ferromagnetic and anti-ferromagnetic (AFM) states of it have been obtained by the calculation. The electronic structure and magnetic coupling between cobalt ions along chain are discussed, and the calculations reveal that the compound [Co(μ1,3-SCN)2(μ1,6-dmpzdo)]n has a stable anti-ferromagnetic ground state, which is in good agreement with the experimental results.  相似文献   

16.
The extended stretch-bender Hamiltonian, incorporating spin-orbit coupling and overall rotation, has been used to calculate the spin-vibronic structure of the X?2B1 state of NH2 up to the barrier to linearity of this state. A detailed comparison has been made with experimental measurements of these rovibronic states, the majority of which are due to Vervloet and his collaborators. We have shown that, in order to fit the variation of the vibronic spin-orbit coupling constant over the whole of this energy regime, the effective linear molecule spin-orbit coupling constant, ASO, must be increased from the earlier value of 50 cm−1 of Ch. Jungen, K.-E. J. Hallin, and A. Merer (Mol. Phys.40, 65-94 (1980)) to 61.6 cm−1. Evidence has also been provided for the large quenching of the spin-orbit coupling as the molecule bends, reflected in the large valuee of gK=6 cm−1. The pattern of calculated spinrovibronic levels, including the effects of spin uncoupling, is in good agreement with that measured experimentally.  相似文献   

17.
The reaction cross section of 17B on 12C target at (43.7±2.4)MeV/u has been measured at the Radioactive Ion Beam Line in Lanzhou (RIBLL). The root-mean-square matter radius (Rrms) was deduced to be (2.92±0.10)fm, while the Rrms of the core and the valence neutron distribution are 2.28fm and 5.98fm respectively. Assuming a ``core plus 2n' structure in 17B, the mixed configuration of (2s1/2) and (1d5/2) of the valence neutrons is studied and the  相似文献   

18.
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   

19.
A semiempirical method of analysis of quasi-molecular terms in conjunction with experimental potentials of interaction of Hg(6(3 P 1)) atoms with Ar, Kr, and Xe atoms are used to obtain the Hg(63 P 2)-Ar, Kr, Xe interaction potential, which are applied to calculating the radiative lifetimes of the v′1(3 P 2) states of the HgAr, HgKr, and HgXe molecules and the probabilities of the v′1(3 P 2)−v″0+(1 S 0) transitions.  相似文献   

20.
35ClO237ClO2
ν0945.592 357(60)939.602 909(66)cm?1
μ′1.788 39(13)1.788 46(15)D
μ″1.791 95(10)1.792 10(13)D
δμ?0.003 56(18)?0.003 64(26)D
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