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1.
The Coriolis interactions between ν1 and ν3, and between ν2 and ν3 in SO2 have been analyzed to obtain the signs of the products ζ3.1c(a?Q3)(b?Q1) and ζ3.2c(a?Q3)(b?Q2). It has been found that both of the signs of these products are positive. Then, relative signs of (?Q1) have been determined using the calculated values of the Coriolis zeta constants for the present definition of the normal coordinates. The obtained sign combination of (?Qi) is ±(+?+), which agrees with the one predicted by the molecular orbital calculations. Using the sign combination (+?+), the polar tensors of S and O atoms were also calculated.  相似文献   

2.
Medium resolution infrared grating spectra of gaseous ketene, H2CCO were recorded between 1000 and 400 cm?1, both at instrument temperature (40°C) and with cooling (?40°C). Interferometric Fourier spectra were also measured at ?70°C with resolution 0.22 cm?1 between 450 and 330 cm?1. The K structure of the fundamentals ν5, ν6, ν8, and ν9 was assigned. These fundamentals are coupled by a-axis Coriolis interactions. These couplings were analysed on the symmetric top basis for setting up the perturbation matrix and by utilizing the K-dependent Coriolis shifts of levels. A preliminary analysis of the Coriolis intensity anomalies was also undertaken.Band center values from combination differences are ν50 = 587.30 (27) and ν60 = 528.36 (39) cm?1. Synthetic spectra indicate the band origins of ν8 and ν9 to be close to 977.8 and 439.0 cm?1, respectively. Estimates of Coriolis coupling constants obtained from synthetic spectra are ζ58a = + 0.33 (5), ζ68a = + 0.714 (20), ζ59a = ? 0.774 (20), and ζ69a = ? 0.30 (2). Approximate ratios of unperturbed vibrational transition moments obtained from spectral simulations are M80:±iM50:±iM60:M90 ≈ +2:?9:+10:+0.5.  相似文献   

3.
The results of a vibrational and rotational analysis of the banded a?3A2X?1A1 transition in CH2SCD2S are presented. Only three of the six vibrational modes are active in the spectrum with ν′2 = 13201012, ν′3 = 859798, and 2ν′4 = 711516cm?1. The spin forbidden transition gains intensity primarily by a mixing of the 1A11,π) and 3A21,n) states. This is confirmed by a rotational analysis of the 000 band of both isotopes. The rotational analysis shows that the coupling in the a?3A2 state is near Hund's case b and that the spin constants are nearly 10 times greater than those observed for CH2O. A CNDO2 calculation shows that this difference is due to the greater spin orbit coupling of S in CH2S and to the smaller energy differences between the B?1A11,π), b?3A11,π), X?1A1, and the a?3A21,n) states. The r0 structure calculated from the rotational constants is rCS = 1.683 A?, rCH = 1.082 A?, βHCH = 119.6°, and α (out of plane) = 16.0°. A simultaneous fit of the vibrational levels in ν4 of CH2S and CD2S to a double minimum potential function yielded a barrier to molecular inversion of 13 cm?1 and an equilibrium out-of-plane angle of 15°.  相似文献   

4.
The non-selective nature of the (α, nγ) reaction has been used to complement information from charged-particle reactions on the level structure of 88Y and 90Y. The γ-ray spectra were recorded with a 25 cm3 Ge(Li) detector at 90° to the beam using primarily targets of 85Rb2CO3 and 87Rb2CO3 and α-particle energies of 11.8, 12.2 and 13.0 MeV. The resulting transitions were accommodated in level schemes that involved primarily the following shell model configurations: p12)1g92)?1, g92)?1g92)1, p12)1p12)?1, f52)?1g92)?1 in 88Y and p12)1d52)1, πg(92)1d52)1,p12)1s12))1 in 90Y.  相似文献   

5.
The J = 2?1 microwave spectrum of six isotopic species of HSiF3 has been observed and assigned in excited states of five of the six fundamental vibrations. The assignment is based on relative intensities, double resonance experiments, and trial anharmonic force constant calculations. Analysis of the spectra leads to experimental values for five of the αrB constants, all three l-doubling constants qt, one Fermi resonance constant φ233, and one zeta constant ζ6, 6(z).The harmonic force field has been refined to all the available data on vibration wavenumbers, centrifugal distortion constants, and zeta constants. The cubic anharmonic force field has been refined to the data on αrB and qt constants, using two models: a valence force model with two cubic force constants for SiH and SiF stretching, and a more sophisticated model. With the help of these calculations, the following equilibrium structure has been determined: re(SiH) = 1.4468(±5) A?, re(SiF) = 1.5624(±1) A?, ∠HSiF = 110.64(±3)°,  相似文献   

6.
The gas phase infrared spectra of monoisotopic H3Si35Cl and H3Si37Cl have been studied in the ν1ν4 region near 2200 cm?1 with a resolution of 0.012 and 0.04 cm?1, respectively, and rotational fine structure for ΔJ = ±1 branches has been resolved. In addition, some information on ν3 + ν4 of H3Si35Cl near 2750 cm?1 has been obtained. ν1 and ν4 are weakly coupled by Coriolis x, y resonance, BΩ14ζ14 ~ 2 × 10?3cm?1, only the upper states K′ = 2, l = 0 and K′ = 1, l = ?1 being substantially affected. Local perturbation due to rotational l(±1, ±1)-type resonance with ν3 + ν5+1 + ν6+1 and ν3 + ν5+1 + ν6?1 is revealed in the ΔK = +1 and ?1 branches, respectively. From a fit of the experimental line positions, standard deviations of 1.4 and 3.8 × 10?3 cm?1, respectively, to a model with five interacting levels conventional excited state parameters and interaction constants have been obtained. In H3Si35ClH3Si37Cl the fundamentals are ν1, 2201.94380(15)2201.9345(7) and ν4, 2209.63862(8)2209.6254(2) cm?1, respectively. Q branches of the “hot” band (ν3 + ν4) ? ν3 and of ν4 of the 29Si and 30Si species have been detected.  相似文献   

7.
The rz structure of phosgene has been determined by a joint analysis of the electron diffraction intensity and the rotational constants as follows: rz(CO) = 1.1785 ± 0.0026 A?, rz(CCl) = 1.7424 ± 0.0013 A?, ∠z;ClCCl = 111.83 ± 0.11°, where uncertainties represent estimated limits of experimental error. The effective constants representing bond-stretching anharmonicity have been obtained from an analysis of the isotopic differences in the rz structure: a3(CO) = 2.9 ± 0.9 A??1, a3(CCl) = 1.6 ± 0.4 A??1. The equilibrium bond distances have been estimated from the rz structure for the normal species and from the anharmonic constants to be re(CO) = 1.1756 ± 0.0032 A?, re(CCl) = 1.7381 ± 0.0019 A?.  相似文献   

8.
The sound velocities in GeS2 glass have been measured by means of ultrasonic interferometry as a function of temperature or pressure up to 1.8 kbar. The bulk modulus Ks = 117.6 kbar and shear modulus G = 60.60 kbar were obtained for GeS2 glass at 15°C and 1 atm. The temperature derivatives of both sound velocities and elastic moduli are negative :
(1?T)
p =
?1.54 × 10?4 kmsec
°C,
(1?T)
p =
?1.27× 10?4 kmsec
°C and
(?Ks?T)
p =
?1.27 × 10?2kbar°C
,
(?G?T)
p = ?1.23 × 10?2 kbar/°C,
(?Y?T)
p = ?2.93 × 10?2 their pressure derivatives are positive:
(1?P)
T = 4.43× 10?2km/kbar,
(1?P)
T =
0.633 × 10?2kmkbar
and (?Ks?P0)T=6.81,
(?G?P)T
= 1.03, (?Y?TT= 3.57. The Grüneisen parameter, γth= 0.298, and the second Grüneisen parameter, δs = 3.27, have also been calculated from these data. The elastic behavior of GeS2 glass has proved to be normal despite the structural similarity among the tetrahedrally coordinated SiO2, GeO2 and GeS2 glasses.  相似文献   

9.
We derive and compare with experimental data the bound
α??λmp?mpν212ν0dν′σtot(ν′)(ν′221)+2πmpν0ν′2dν′σtot(ν′)(ν′221){ν′2(dσdt)0+πλ2+2ν′|λ|π(dσdt)0?σ2tot16π}?1
, where α is the fine-structure constant, mp the proton mass, ν0 the photo-pion production threshold, σtot and (dσdt)0 are the unpolarized total hadronic photo-absorption cross section on protons and the unpolarized forward differential cross section for proton Compton scattering at photon-lab energy ν′, and λ and ν1 are any real numbers. We derive similar bounds on proton and neutron magnetic moments.  相似文献   

10.
The Raman active fundamentals ν1(A1g), ν2(Eg), ν5(F2g), and the overtone 2ν6 of SF6 have been investigated with a higher resolution and the band origins were estimated to be: ν1 = 774.53 cm?1, ν2 = 643.35 cm?1, ν5 = 523.5 cm?1, and 2ν6 = 693.8 cm?1. Raman and infrared data have been combined for estimation of several anharmonicity constants. The ν6 fundamental frequency is calculated as 347.0 cm?1. From the analysis of the ν2 Raman band, the following rotational constants of both the ground and upper states have been calculated:
B0 = 0.09111 ± 0.00005cm?1; D0 = (0.16±0.08)10?7cm?1
;
B2 = 0.09116 ± 0.00005cm?1; D2 = (0.18±0.04)10?7cm?1
.  相似文献   

11.
A millimeter-wave spectrometer having a sensitivity of 4 × 10?10 cm?1 in the 2-mm region has been constructed for observation of extremely weak millimeter-wave spectra of gases. It has been used to measure JJ, K = 0 ← 3 transitions in PH3 and JJ, K = 0 ← 3 as well as K = ±1 ← ±4 transitions in PD3. The B0 and C0 spectral constants (in MHz) are: for PH3, B0 = 133 480.15 ± 0.12 and C0 = 117 488.85 ± 0.16; for PD3, B0 = 69 471.10 ± 0.03 and C0 = 58 974.37 ± 0.05. The effective ground-state values obtained for the bond angle and bond length are: for PH3, r0 (A?) = 1.4200 and α0(o) = 93.345; for PD3, r0 (A?) = 1.4176 and α0(o) = 93.359. The corresponding zero-point-average values were calculated to be: for PH3, rz (A?) = 1.42699 ± 0.0002 and αz(o) = 93.2287; for PD3, rz (A?) = 1.42265 ± 0.0001 and αz(o) = 93.2567 ± 0.004. For both species, the equilibrium values are re (A?) = 1.41159 ± 0.0006 and αe(o) = 93.328 ± 0.02.  相似文献   

12.
Charge properties of the hadronic systems from νp and νp scattering in BEBC are studied in the framework of the quark-parto model (QPM). The average charges 〈Qjetν and 〈Qjetν of a quark jet and a d-qua jet, respectively, are determined according to two different methods. The difference 〈Qjetν ? 〈Qjetν is in agreement with e QPM value of 1. Scaling of charge and energy flow in the angular variable λ is demonstrated. The ratios ΔQν/ΔQν of charge flows in νp a νp scattering are in accord with the QPM in both hemispheres.  相似文献   

13.
The average multiplicity in deep inelastic electro- and neutrinoproduction at large ω(ωs/Q2 + 1) is related in Feynman's version of the parton model to the average multiplicities in high-energy electron-positron annihilation and hadron-hadron scattering. The relation is: 〈n(s, Q2)〉ePP ~ Ce+e?ln(Q2M1⊥2) + Chln(ω ? 1), where Ce+e? and Ch are, respectively, the coefficients of ln(s/M1⊥2) in the multiplicities from e+-e? and P-P in to hadrons, and M1⊥ is an average transverse mass.  相似文献   

14.
D.J. Gates 《Physica A》1975,81(1):47-71
The k-particle, infinite-volume distribution functions n?k (r1, …, rk?1, γ) and modified Ursell correlation functions U?k (r1, …, rk?1, γ) of a classical system of particles with the two-body potential q(r) + γνK(γr) are considered. The limiting values of the functions n?k (r1, …, rk?1, γ), n?k (S1/γ, …, Sk?1/γ, γ) and γ(1?kU?k (S1/γ, …, Sk?1/γ, γ) in the limit γ → 0 are calculated, under fairly weak conditions on q and K, by a method involving functional differentiation. These limiting functions are used to describe the molecular structure of the various states of the system both in the range of the potential q(r) and in the rage of the potential γνKr). The direct correlation function c? (r, γ) is also considered and it is shown that for S ≠ 0, limγ→0 γc? (Sγ, γ) = ?βK (S), for all one-phase states, where β is the reciprocal temperature. Special cases of our results confirm those of other authors, including the well-known results of Ornstein and Zernike.  相似文献   

15.
Line strengths and self- and nitrogen-broadened half-widths were measured for spectral lines in the ν3 and ν2 + ν4 bands of 12CH4 and 13CH4 from 2870–2883 cm?1 using a tunable diode laser spectrometer. From measurements made over a temperature range from 215 to 297 K, on samples of 12CH4 broadened with N2, we deduced that the average temperature coefficients n, defined as bL0(T) = bL0(T0)(TT0)?n, of the Lorentz broadening coefficients for the ν3 and ν2 + ν4 bands of 12CH4 were 0.97 ± 0.03 and 0.89 ± 0.04, respectively. A smaller increase is observed in line half-width with increasing pressure for E-species lines, for both self- and nitrogen-broadening, than for other symmetry species lines over the range of pressures measured, 70 to 100 Torr.  相似文献   

16.
It is shown that for spinorial charges Q(L))α (α = 1, 2, L = 1, …, S) satisfying the commutation relations
{Q(L)α, Q(M)β} = εαβaLMQ,
{Q(L)α, Q(M)+β} = cσμαβPμδLM,
[Q(L))α, Pμ] = 0,
where Q is a scalar charge commuting with the spinor charges as well aswith the energy- momentum vector Pμ, there can exist several different multiplets for free massive scalar and spinor fields.  相似文献   

17.
Approximate experimental and theoretical information about vibronic coupling of the X?2A1 (ground) and A?2B2 electronic states of NO2—by its antisymmetric vibration ν3(b2)—is tested in model calculations of the accurately known ground-state levels ν3 = 0, 1, 2, 3. The test is positive and it is estimated that 64% of the very large observed anharmonic constant χ33 has its origin in vibronic coupling. In this model, ν3 in the à state is predicted at about 1200 cm?1.  相似文献   

18.
The bending vibration bands ν4 and ν5 of HCCI were studied. From the observed rotational structure the rotational constant B0 and the centrifugal distortion constant D0 were obtained. The results were B0 = 0.105968(7) cm?1 and D0 = 1.96(7) × 10?8 cm?1 from ν4 and B0 = 0.105948(8) cm?1 and D0 = 1.96(11) × 10?8 cm?1 from ν5. The structure of the hot bands 2ν5(Δ) ← ν5(Π) and 3ν5(φ) ← 2ν5(Δ) was also resolved and hence the values α5 = ?3.033(8) × 10?4 cm?1 and q5 = 9.3(3) × 10?5 cm?1 could be derived. The other most intense hot bands following ν5 could be explained in terms of the Fermi diads ν350 and ν3 + ν5±15±1. Of the numerous hot bands accompanying ν4, only those between different excited states of ν4 could be assigned. Then estimates for α4 and q4 were also obtained. In addition, several vibrational constants were derived.  相似文献   

19.
The pure rotational spectra of three deuterated ethylenes, CH2CD2, CH2CHD, and cis-CHDCHD, were observed by microwave spectroscopy, and the rotational and centrifugal distortion constants were determined precisely. The dipole moment of CH2CD2 was calculated from the Stark effects to be 0.0091 ± 0.0004 D. From the observed rotational constants the average structure was calculated to be rz(CC) = 1.3391 ± 0.0013 A?, rz(CH) = 1.0869 ± 0.0013 A?, θz(CCH) = 121.28 ± 0.10°, and rz(CH) - rz(CD) = 0.00137 ± 0.00037 A?, where the errors include one standard deviation in the fitting and errors due to an uncertainty (±0.03°) in θz(CCH) - θz(CCD).  相似文献   

20.
The 91Zr(d, 3He) reaction was studied at a deuteron energy of 28 MeV. Angular distributions were measured from 13° to 47°; lp values were extracted for the prominent lines of 90Y. The lp values and transition strengths were determined by DWBA analysis. The angular distributions for the p12)(νd52) doublet (g.s. and 0.20 MeV state) exhibit the characteristic l = 1 shape. States at 1.42, 1.57, 1.64 and 1.81 MeV were also populated strongly in the (d, 3He) reaction; the 1.42, 1.57 and 1.81 MeV levels contain l= 1 transition strength and are most likely members of the p32?1)(νd52) multiplet. The 2.03 MeV state has a characteristic l = 3 angular distribution and is suggested to be the only member of the f32?1)(νd52) sextet to be unambiguously observed in this study, most probably the 5? or 4? member. The members of the g52)(νd92) sextet were populated weakly (less than 100 μb/sr) in this reaction.  相似文献   

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