CO2 and N2O laser Stark spectroscopy of the ν1 band of the ClO2 radical

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

     

2.

Rovibrational analysis of the ν₂ and 2ν₂ P-D stretching bands of PH₂D     

O.N. Ulenikov  O.L. Khabibulina  E.S. Bekhtereva  H. Bürger 《Journal of Molecular Spectroscopy》2003,217(2):288-297

The infrared spectral regions of the P-D stretching fundamental band ν₂ and the first overtone band 2ν₂ of PH₂D were recorded with a resolution of 2.7×10⁻³ and , respectively. In the analysis about 710 and 440 transitions were assigned to the ν₂ and 2ν₂ bands. These provided 358 and 268 upper rovibrational energy terms, respectively. Resonance interactions between the states (010000) and (000200) were taken into account in the Hamiltonian used to fit upper energies of the (010000) state. The rovibrational energies of the (020000) state were fitted with a Hamiltonian for an isolated vibrational state.     

3.

Infrared spectra of two isomers of OCS-C₂H₂ and OCS-C₂D₂ in the region of OCS ν₁ fundamental     

J. Norooz Oliaee  M. Dehghany  A.R.W. McKellar 《Journal of Molecular Spectroscopy》2009,257(2):133-10422

Infrared spectra of OCS-C₂H₂ and OCS-C₂D₂ complexes in the region of the C-O stretching fundamental of OCS (∼2060 cm⁻¹) are studied in a pulsed supersonic slit-jet expansion using a tunable diode laser. For each complex, two bands are observed and assigned to distinct near-parallel and the T-shaped isomers. Ground state parameters were previously determined from microwave studies, so analysis of the infrared spectra gives information on the vibrational shifts upon complex formation as well as rotational and centrifugal distortion parameters for the excited states. All four bands show a red shift with respect to the monomer band origin, with the T-shaped isomer having a much larger shift than the near-parallel isomer. Disappearance of the T-shaped isomer when argon is used as a carrier gas supports the notion that the near-parallel isomer is the lowest energy form of the complex.     

4.

Renormalization of the band parameters owing to the phonon interaction in Bi₂Sr₂CaCu₂O_{8 ? x} and determination of the superconducting gap parameters from the temperature dependence of the superconducting current density in YBa₂Cu₃O₇     

M. V. Eremin  M. A. Malakhov  D. A. Sunyaev 《JETP Letters》2012,96(2):105-108

     

5.

High-resolution infrared analysis of the ν₇ band of cis-ethylene-d₂ (cis-C₂H₂D₂)     

T.L. Tan  G.B. Lebron 《Journal of Molecular Spectroscopy》2010,261(2):87-90

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 I^r 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.     

6.

Analysis of the hot bands in the 2ν₉ band region of propyne-d₃     

Geetha Rajappan 《Journal of Molecular Spectroscopy》2004,224(2):107-113

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.     

7.

Bifurcations of the normal modes of the Ne?Br₂ complex     

Fernando Blesa  J. Pablo Salas 《Physics letters. A》2009,374(2):191-201

We study the classical dynamics of the rare gas-dihalogen Ne?Br₂ complex in its ground electronic state. By considering the dihalogen bond frozen at its equilibrium distance, the system has two degrees of freedom and its potential energy surface presents linear and T-shape isomers. We find the nonlinear normal modes of both isomers that determine the phase space structure of the system. By means of surfaces of section and applying the numerical continuation of families of periodic orbits, we detect and identify the different bifurcations suffered by the normal modes as a function of the system energy. Finally, using the Orthogonal Fast Lyapunov Indicator (OFLI), we study the evolution of the fraction of the phase space volume occupied by regular motions.     

8.

The high resolution FTIR spectrum of the ν₂ band of formaldehyde isotopomer H₂CO     

T.L. Tan  G.B. Lebron 《Journal of Molecular Spectroscopy》2011,270(1):79-82

The Fourier transform infrared (FTIR) absorption spectrum of the ν₂ fundamental band of the formaldehyde isotopomer H₂¹³CO was recorded at an unapodized resolution of 0.0063 cm⁻¹ in the 1630–1780 cm⁻¹ region. Upper state (ν₂ = 1) rovibrational constants inclusive of three rotational, five quartic, and six sextic centrifugal distortion constants were accurately determined by assigning and fitting 447 unperturbed infrared transitions with a rms deviation of 0.00056 cm⁻¹ using Watson’s A-reduced Hamiltonian in the I^r representation. Analysis of new transitions measured in this work yielded more higher-order upper state constants with greater accuracy than previously reported. The band center of the A-type ν₂ band was found to be 1707.980943 ± 0.000058 cm⁻¹ while the calculated inertial defect Δ₂ of the H₂¹³CO molecule was 0.09581 ± 0.00004 μŲ.     

9.

Infrared diode laser spectroscopy of the ν₃ fundamental band of the PO₂ free radical     

Michael A. Lawson  Kristian J. Hoffman  Paul B. Davies 《Journal of Molecular Spectroscopy》2011,269(1):61-76

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.     

10.

High resolution study of the 3ν₁ band of SO₂     

O.N. Ulenikov  E.S. Bekhtereva  S. Alanko 《Journal of Molecular Spectroscopy》2009,255(2):111-121

The second overtone band 3ν₁ of sulfur dioxide has been studied for the first time with high resolution rotation-vibration spectroscopy. About 3000 transitions involving about 900 upper state energy levels with have been assigned to the 3ν₁ band. In the analysis, an effective Hamiltonian taking into account accidental interactions between the vibrational states (3 0 0), (2 2 0), and (0 4 1) was used. The Watson operator in A-reduction and I^r representation was used in the diagonal blocks of the Hamiltonian. As the result of analysis a set of parameters reproducing the initial experimental data with the rms = 0.00028 cm⁻¹ was obtained.     

11.

Kinetics of the apparent isothermal and non-isothermal crystallization of the α-Fe phase within the amorphous Fe₈₁B₁₃Si₄C₂ alloy     

Borivoj Adna?evi?  Bojan Jankovi?  Dragica M. Mini? 《Journal of Physics and Chemistry of Solids》2010,71(7):927-985

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 n_iso=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.     

12.

Molecular-Gas-Pressure-Induced Line-Shift and Line-Broadening in the ν₂-Band of H₂S     

A KisselB Sumpf  H.-D KronfeldtB.A Tikhomirov  Yu.N Ponomarev 《Journal of Molecular Spectroscopy》2002,216(2):345-354

The pressure-induced shift and broadening of H₂S absorption lines in the ν₂-band due to collisions between H₂S molecules and quadrupole molecules, such as O₂, H₂, D₂, N₂, and CO₂, were studied in the spectral region between 1050 and 1325 cm⁻¹. The measurements were carried out using a pulse-driven diode laser spectrometer with two multipass Herriott cells. The data concerning the collisional broadening and shift coefficients, γ and δ, respectively, and their dependencies on the rotational quantum number J″ and the quadrupole moment Q of the molecular perturber are presented for 14 P-branch transitions (3≤J″≤8,0≤K_a^Prime;≤3, 2≤K_c^Prime;≤8), 7 Q-branch transitions (7≤J^Prime;≤10, 1≤K_a^Prime;≤2, 6≤K_c^Prime;≤9), and 18 R-branch transitions (2≤J^Prime;≤11, 0≤K_a^Prime;≤4, 0≤K_c^Prime;≤11). The broadening coefficients γ were determined with an accuracy to within 2% and shift coefficients δ were determined with an uncertainty of less than 10⁻³ cm⁻¹/atm for the majority of lines and broadening gases.     

13.

Stretch-Bender Calculations of the Rovibronic Energies in the Excited, ÃA₁, Electronic State of NH₂ and of the Near-Resonant High-Lying Levels of the X?B₁ State     

Geoffrey DuxburyAlexander Alijah 《Journal of Molecular Spectroscopy》2002,211(1):31-57

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 òA₁ 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, A_SO 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 òA₁ 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.     

14.

Stretch-Bender Calculations of the Rovibronic Energies in the X?B₁ Electronic Ground State of NH₂     

Alexander Alijah  Geoffrey Duxbury 《Journal of Molecular Spectroscopy》2002,211(1):16-30

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, A_SO, 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 g_K=6 cm⁻¹. The pattern of calculated spinrovibronic levels, including the effects of spin uncoupling, is in good agreement with that measured experimentally.     

15.

Influence of hydrothermally modified γ-Al₂O₃ on the properties of NiMo/γ-Al₂O₃ catalyst     

Juncheng Li  Lan Xiang  Xu Feng 《Applied Surface Science》2008,254(7):2077-2080

The influence of hydrothermal modification of γ-Al₂O₃ on the properties of NiMo/γ-Al₂O₃ catalyst was investigated in this paper. The experimental results showed that the use of the modified γ-Al₂O₃ in the preparation of the NiMo/γ-Al₂O₃ catalyst led to the increase of the dispersion of the surface Mo and Ni oxides, favored the formation of the poly-molybdates and promoted the reduction of the active Mo oxides owing to the increase of the surface acidity of the modified γ-Al₂O₃. Therefore, the NiMo/γ-Al₂O₃ catalyst supported on the modified γ-Al₂O₃ exhibited a higher hydrodenitrogenation (HDN) activity than that supported on the untreated γ-Al₂O₃ in the temperature range of 300-340 °C.     

16.

Influence of relaxation effects on probabilities of the 2s2p³⁵S₂－2s²2p^{2 3}P_1，2 intercombination transitions in NII          下载免费PDF全文

袁萍  刘欣生  颉录有  张义军  董晨钟 《中国物理》2003,12(3):271-274

Transition probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} intercombination transitions in NII have been calculated by using a large-scale multiconfiguration Dirac－Fock method. In the calculation the most important effects of relativity, correlation, and relaxation are considered. From the calculated transition probabilities, the lifetime of the 2s2p^3 {}^5S_2 metastable state is derived. The result is in excellent agreement with the latest experimental result. In the meantime the influence of anomalously strong relaxation effects on probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} lines in NII have been found.     

17.

Q²-Rescaling Parameters’Empiric Formula of the Double Q²-Rescaling Model          下载免费PDF全文

GAO Yong-Hua  HE Ming-Zhong  DUAN Chun-Gui 《中国物理C(英文版)》2001,25(6):533-537

We presented a Q²-rescaling parameters′empiric formula of the Q²-rescaling model, in which we established the connection between the Q²-rescaling parameters ξ_i(i=V,S,G) and the mean binding energy in nucleus. By using the formula, we can get the Q²-rescaling parameters for various nuclei with A>12, and thus further calculate the relevant nuclear process and make out prediction.     

18.

The high-resolution FTIR spectrum of the ν₆ band of C₂H₃D     

T.L. Tan  G.B. Lebron 《Journal of Molecular Spectroscopy》2010,263(2):160-165

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 I^r 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 (μ_a/μ_b) 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 μŲ.     

19.

Diode laser spectroscopy of the ν₂ fundamental band of cis-HOPO     

P.J. O’Sullivan  P.B. Davies  J.M. Turney 《Journal of Molecular Spectroscopy》2006,235(2):248-260

The absorption spectrum of the ν₂ fundamental band of the cis-conformer of the transient molecule HOPO, namely the terminal PO stretching mode, has been detected and measured using diode laser spectroscopy. The molecule was generated in a discharge flow system containing hydrogen and white phosphorus vapour (P₄) and a trace of oxygen. The spectrum has the appearance of an a-type band of a near prolate asymmetric top. Above K_a = 5 the spectrum is perturbed and transitions terminating on these higher K_a levels were excluded from the fit. The vibrational frequency and rotational constants derived from the unperturbed parts of the spectrum are compatible with new high precision ab initio calculations reported here. A combined fit of the ν₂ band and the ν₄ band data, measured earlier, was carried out. The ν₂ band origin was determined to be 1258.539525(32) cm⁻¹, approximately 5.5 cm⁻¹ higher than the matrix value.     

20.

Study of hot bands in the B²Σ⁺_u-X²Σ⁺_g system of C^-₂ anion          下载免费PDF全文

喻姗姗  杨晓华  李本霞  Kaniki Kakule  吴升海  郭迎春  刘煜炎  陈扬骎 《中国物理》2003,12(7):745-749

Optical heterodyne magnetic rotation enhanced velocity modulation spectroscopy was employed to observe the visible absorption spectra of the B^2Σ^+_u-X^2Σ^+_g electronic transition of C^-_2. Four hot bands (0,1), (1,2), (2,3) and (3,4) have been observed and the band (3,4) is measured directly for the first time, so far as we know, by absorption. A rotational analysis was carried out to obtain molecular constants. With the Franck－Condon principle and the vibrational Boltzmann distribution, we have estimated the vibrational temperature of C^-_2 to be about 3000K.     

		35ClO2		37ClO2
$\text{ν}{}_0$		945.592 357(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

Rovibrational analysis of the ν2 and 2ν2 P-D stretching bands of PH2D

The infrared spectral regions of the P-D stretching fundamental band ν₂ and the first overtone band 2ν₂ of PH₂D were recorded with a resolution of 2.7×10⁻³ and , respectively. In the analysis about 710 and 440 transitions were assigned to the ν₂ and 2ν₂ bands. These provided 358 and 268 upper rovibrational energy terms, respectively. Resonance interactions between the states (010000) and (000200) were taken into account in the Hamiltonian used to fit upper energies of the (010000) state. The rovibrational energies of the (020000) state were fitted with a Hamiltonian for an isolated vibrational state.     

Infrared spectra of two isomers of OCS-C2H2 and OCS-C2D2 in the region of OCS ν1 fundamental

Infrared spectra of OCS-C₂H₂ and OCS-C₂D₂ complexes in the region of the C-O stretching fundamental of OCS (∼2060 cm⁻¹) are studied in a pulsed supersonic slit-jet expansion using a tunable diode laser. For each complex, two bands are observed and assigned to distinct near-parallel and the T-shaped isomers. Ground state parameters were previously determined from microwave studies, so analysis of the infrared spectra gives information on the vibrational shifts upon complex formation as well as rotational and centrifugal distortion parameters for the excited states. All four bands show a red shift with respect to the monomer band origin, with the T-shaped isomer having a much larger shift than the near-parallel isomer. Disappearance of the T-shaped isomer when argon is used as a carrier gas supports the notion that the near-parallel isomer is the lowest energy form of the complex.     

High-resolution infrared analysis of the ν7 band of cis-ethylene-d2 (cis-C2H2D2)

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 I^r 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.     

Analysis of the hot bands in the 2ν9 band region of propyne-d3

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.     

Bifurcations of the normal modes of the Ne?Br2 complex

We study the classical dynamics of the rare gas-dihalogen Ne?Br₂ complex in its ground electronic state. By considering the dihalogen bond frozen at its equilibrium distance, the system has two degrees of freedom and its potential energy surface presents linear and T-shape isomers. We find the nonlinear normal modes of both isomers that determine the phase space structure of the system. By means of surfaces of section and applying the numerical continuation of families of periodic orbits, we detect and identify the different bifurcations suffered by the normal modes as a function of the system energy. Finally, using the Orthogonal Fast Lyapunov Indicator (OFLI), we study the evolution of the fraction of the phase space volume occupied by regular motions.     

The high resolution FTIR spectrum of the ν2 band of formaldehyde isotopomer H2CO

The Fourier transform infrared (FTIR) absorption spectrum of the ν₂ fundamental band of the formaldehyde isotopomer H₂¹³CO was recorded at an unapodized resolution of 0.0063 cm⁻¹ in the 1630–1780 cm⁻¹ region. Upper state (ν₂ = 1) rovibrational constants inclusive of three rotational, five quartic, and six sextic centrifugal distortion constants were accurately determined by assigning and fitting 447 unperturbed infrared transitions with a rms deviation of 0.00056 cm⁻¹ using Watson’s A-reduced Hamiltonian in the I^r representation. Analysis of new transitions measured in this work yielded more higher-order upper state constants with greater accuracy than previously reported. The band center of the A-type ν₂ band was found to be 1707.980943 ± 0.000058 cm⁻¹ while the calculated inertial defect Δ₂ of the H₂¹³CO molecule was 0.09581 ± 0.00004 μŲ.     

Infrared diode laser spectroscopy of the ν3 fundamental band of the PO2 free radical

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.     

High resolution study of the 3ν1 band of SO2

The second overtone band 3ν₁ of sulfur dioxide has been studied for the first time with high resolution rotation-vibration spectroscopy. About 3000 transitions involving about 900 upper state energy levels with have been assigned to the 3ν₁ band. In the analysis, an effective Hamiltonian taking into account accidental interactions between the vibrational states (3 0 0), (2 2 0), and (0 4 1) was used. The Watson operator in A-reduction and I^r representation was used in the diagonal blocks of the Hamiltonian. As the result of analysis a set of parameters reproducing the initial experimental data with the rms = 0.00028 cm⁻¹ was obtained.     

Kinetics of the apparent isothermal and non-isothermal crystallization of the α-Fe phase within the amorphous Fe81B13Si4C2 alloy

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 n_iso=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.     

Molecular-Gas-Pressure-Induced Line-Shift and Line-Broadening in the ν2-Band of H2S

The pressure-induced shift and broadening of H₂S absorption lines in the ν₂-band due to collisions between H₂S molecules and quadrupole molecules, such as O₂, H₂, D₂, N₂, and CO₂, were studied in the spectral region between 1050 and 1325 cm⁻¹. The measurements were carried out using a pulse-driven diode laser spectrometer with two multipass Herriott cells. The data concerning the collisional broadening and shift coefficients, γ and δ, respectively, and their dependencies on the rotational quantum number J″ and the quadrupole moment Q of the molecular perturber are presented for 14 P-branch transitions (3≤J″≤8,0≤K_a^Prime;≤3, 2≤K_c^Prime;≤8), 7 Q-branch transitions (7≤J^Prime;≤10, 1≤K_a^Prime;≤2, 6≤K_c^Prime;≤9), and 18 R-branch transitions (2≤J^Prime;≤11, 0≤K_a^Prime;≤4, 0≤K_c^Prime;≤11). The broadening coefficients γ were determined with an accuracy to within 2% and shift coefficients δ were determined with an uncertainty of less than 10⁻³ cm⁻¹/atm for the majority of lines and broadening gases.     

Stretch-Bender Calculations of the Rovibronic Energies in the Excited, ÃA1, Electronic State of NH2 and of the Near-Resonant High-Lying Levels of the X?B1 State

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 òA₁ 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, A_SO 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 òA₁ 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.     

Stretch-Bender Calculations of the Rovibronic Energies in the X?B1 Electronic Ground State of NH2

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, A_SO, 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 g_K=6 cm⁻¹. The pattern of calculated spinrovibronic levels, including the effects of spin uncoupling, is in good agreement with that measured experimentally.     

Influence of hydrothermally modified γ-Al2O3 on the properties of NiMo/γ-Al2O3 catalyst

The influence of hydrothermal modification of γ-Al₂O₃ on the properties of NiMo/γ-Al₂O₃ catalyst was investigated in this paper. The experimental results showed that the use of the modified γ-Al₂O₃ in the preparation of the NiMo/γ-Al₂O₃ catalyst led to the increase of the dispersion of the surface Mo and Ni oxides, favored the formation of the poly-molybdates and promoted the reduction of the active Mo oxides owing to the increase of the surface acidity of the modified γ-Al₂O₃. Therefore, the NiMo/γ-Al₂O₃ catalyst supported on the modified γ-Al₂O₃ exhibited a higher hydrodenitrogenation (HDN) activity than that supported on the untreated γ-Al₂O₃ in the temperature range of 300-340 °C.     

Influence of relaxation effects on probabilities of the 2s2p35S2－2s22p2 3P1，2 intercombination transitions in NII

Transition probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} intercombination transitions in NII have been calculated by using a large-scale multiconfiguration Dirac－Fock method. In the calculation the most important effects of relativity, correlation, and relaxation are considered. From the calculated transition probabilities, the lifetime of the 2s2p^3 {}^5S_2 metastable state is derived. The result is in excellent agreement with the latest experimental result. In the meantime the influence of anomalously strong relaxation effects on probabilities of the 2s2p^3 {}^5S_2－2s^22p^2 {}^3P_{1,2} lines in NII have been found.     

Q2-Rescaling Parameters’Empiric Formula of the Double Q2-Rescaling Model

We presented a Q²-rescaling parameters′empiric formula of the Q²-rescaling model, in which we established the connection between the Q²-rescaling parameters ξ_i(i=V,S,G) and the mean binding energy in nucleus. By using the formula, we can get the Q²-rescaling parameters for various nuclei with A>12, and thus further calculate the relevant nuclear process and make out prediction.     

The high-resolution FTIR spectrum of the ν6 band of C2H3D

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 I^r 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 (μ_a/μ_b) 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 μŲ.     

Diode laser spectroscopy of the ν2 fundamental band of cis-HOPO

The absorption spectrum of the ν₂ fundamental band of the cis-conformer of the transient molecule HOPO, namely the terminal PO stretching mode, has been detected and measured using diode laser spectroscopy. The molecule was generated in a discharge flow system containing hydrogen and white phosphorus vapour (P₄) and a trace of oxygen. The spectrum has the appearance of an a-type band of a near prolate asymmetric top. Above K_a = 5 the spectrum is perturbed and transitions terminating on these higher K_a levels were excluded from the fit. The vibrational frequency and rotational constants derived from the unperturbed parts of the spectrum are compatible with new high precision ab initio calculations reported here. A combined fit of the ν₂ band and the ν₄ band data, measured earlier, was carried out. The ν₂ band origin was determined to be 1258.539525(32) cm⁻¹, approximately 5.5 cm⁻¹ higher than the matrix value.     

Study of hot bands in the B2Σ+u-X2Σ+g system of C-2 anion

Optical heterodyne magnetic rotation enhanced velocity modulation spectroscopy was employed to observe the visible absorption spectra of the B^2Σ^+_u-X^2Σ^+_g electronic transition of C^-_2. Four hot bands (0,1), (1,2), (2,3) and (3,4) have been observed and the band (3,4) is measured directly for the first time, so far as we know, by absorption. A rotational analysis was carried out to obtain molecular constants. With the Franck－Condon principle and the vibrational Boltzmann distribution, we have estimated the vibrational temperature of C^-_2 to be about 3000K.