SO5 SU2 SU2 U1 U1及SO5 U1 U1的矢量相干态表示

本文讨论了SO₅ SU₂ SU₂ U₁ U₁及SO₅ U₁ U₁的VCS表示.计算了SO₅ U₂ U₂的约化矩阵元,并利用K矩阵技术确定了SO₅权的多重度.     

Li2K(IO3)3与Li2NH4(IO3)3的晶体结构

本文用X射线粉末法测定了Li₂K(IO₃)₃与Li₂NH₄(IO₃)₃的晶体结构和原子参数。发现Li₃K(IO₃)₃,Li₂NH₄(IO₃)₃与Li₂Rb(IO₃)₃同晶型,属单斜晶系,空间群为P2₁/α,每个单胞含有四个化合式量。室温的点阵常数分别为α=11.198?,b=11.046?,c=8.254?,β=111.53°,及α=11.327?,b=11.078?,c=8.341?,β=111.87°。讨论了二元化合物的形成与离子半径的关系。 关键词：     

Mg2(BH4)2(NH2)2脱氢机理的理论研究

对Mg₂(BH₄)₂(NH₂)₂的脱氢机理展开系统的理论研究发现相对于分子内的脱氢过程,分子间的脱氢过程在热力学和动力学方面都是比较有利的. Mg₂(BH₄)₂(NH₂)₂脱氢过程的第一步是BH₄^-中的B-H^δ-和NH2-中     

合成反铁磁Ni81Fe19/Co90Fe10/Ru/Co90Fe10/Ni81Fe19的研究

采用直流磁控溅射方法制备了一系列的合成反铁磁及以其为自由层的自旋阀.研究发现,在Ni₈₁Fe₁₉与Ru层之间插入适当厚度的Co₉₀Fe₁₀层后,可有效地提高合成反铁磁两磁性层间的反铁磁耦合强度,得到具有饱和场H_s更高、饱和磁化强度M_s更低、热稳定性更好的合成反铁磁.另外,以这种合成反铁磁作自旋阀的自由层时,可有效提高自旋阀的稳定性. 关键词： 合成反铁磁 退火 自旋阀     

正磷酸盐晶体Ba3(PO4)2和Sr3(PO4)2高温拉曼光谱研究

测量了碱土金属正磷酸盐Ba₃(PO₄)₂和Sr₃(PO₄)₂常温及高温拉曼光谱, 对拉曼振动模式进行指认, 并分析了晶体拉曼振动光谱及晶体结构在高温下的变化. 在温度升高的过程中, 拉曼振动频率向低频移动且振动峰宽度展宽, 晶体中的P-O平均键长随温度升高而变长, 但O-P-O的键角并未发生变化. 晶体在900 ℃以下无结构相变发生. 关键词： 3(PO₄)₂和Sr₃(PO₄)₂')" href="#">Ba₃(PO₄)₂和Sr₃(PO₄)₂ 高温拉曼光谱 振动模式 高温结构     

CH4/H2和CH4/He体系等离子体发射光谱分析

 在CH₄/H₂和CH₄/He和CH₄/He两种系统中,利用光学发射谱技术对螺旋波放电产生低压甲烷等离子体内活性粒子的光学发射特征进行了原位诊断。在实验中,两种体系下同时都测得的主要荷电粒子为CH,Ha,Hb,Hg以及H2等。研究了各实验参数对这些活性粒子CH, Ha,Hb以及Hg的发射光谱强度的影响。结果表明：在CH₄/H₂体系下,随着射频功率的增大,Ha,Hb,Hg以及CH基团的相对强度都随着增加,而当放电气压变化时它们都呈现先增大而后减小的趋势。在CH₄/He体系下,随射频功率的增加,Ha,Hb,Hg以及CH相对强度变化的总体趋势也都是先增加而后减小,当工作气压增加时,Ha,Hb以及Hg的相对强度变化也是呈现先增大而后减小,但CH基团的相对强度却是逐渐减小的;这些结果为等离子体沉积各种薄膜过程的理解及制备工艺参数的调整提供了参考。     

Observation of simultaneous ν1(SF6) + ν3(NF3) and ν2(SF6) + ν3(NF3) transitions enhanced by the resonance dipole-dipole interaction with the ν1 + ν3 and ν2 + ν3 states of the SF6 molecule

IR spectra of the solution of SF₆ molecules in liquid NF₃ at 84 K have been recorded. In a solvent transmission window of 1500–1750 cm⁻¹, two wide absorption bands with pronounced peaks in the high-frequency part are observed. The profile of these bands is explained by the influence of the resonance dipole-dipole (RDD) interaction of the states of the simultaneous transition ν₁(SF₆) + ν₃(NF₃) and ν₂(SF₆) + ν₃(NF₃) with the states (ν₁ + ν₃) and (ν₂ + ν₃) of the SF₆ molecules, respectively. The use of three isotopic modifications ³²SF₆, ³³SF₆, and ³⁴SF₆ has allowed us to vary the resonance detuning and thus to change the strength of the RDD interaction. With the liquid near the melting point being represented as a close-packed cubic crystal, the profile was calculated and its spectral characteristics were determined. The frequencies of the main peaks coincide with the experimental values accurate to the error.     

(NH4)2SO4，NH4NO3和(NH4)2SO4/NH4NO3混合气溶胶吸湿质量增长因子的快速测量方法

气溶胶颗粒的吸湿性决定了其尺寸、浓度、化学组成以及相态,从而显著影响着全球气候、大气异相化学以及人类健康。运用在线、原位、连续扫描衰减全反射傅里叶变换红外光谱（ATR-FTIR）技术, 结合线性湿度（RH）控制系统,实现了RH连续变化条件下气溶胶FTIR-ATR光谱的快速测量。根据水弯曲振动谱带（~1 640 cm-1）峰面积随RH的变化,得到了(NH₄)₂SO₄,NH₄NO₃和(NH₄)₂SO₄/NH₄NO₃混合气溶胶的质量增长因子（MGFs）、潮解点（DRH）和风化点（ERH）。与气溶胶的E-AIM模型预测值相比较,实验结果表现出良好的一致性,证实该方法是一种测量大气气溶胶MGFs,ERH和DRH的快速测量方法。     

SU3 U1 U1的矢量相干态表示

本文讨论了U₃的矢量相干态表示.利用K矩阵技术得到了SU₃ U₁ U₁的正交基矢,从而确定了权的多重度.     

High-resolution study of the ν1/ν5 and 2ν1/ν1+ν5 P-H stretching bands of PH2D

The P-H stretching bands ν₁/ν₅ and 2ν₁/ν₁+ν₅ were recorded using a Bruker 120 HR interferometer with a resolution of 0.0042 and 0.0088 cm⁻¹, respectively, and analyzed. From the fits 33 and 50, respectively, vibrational, rotational, centrifugal distortion, and resonance interaction parameters were obtained. These reproduce 668 and 497 rovibrational energies of the pairs of states ν₁/ν₅ and 2ν₁/ν₁+ν₅ with experimental accuracies, rms=0.00016 and , respectively. “Local mode” behavior of the PH₂ fragment is established and discussed in detail.     

The magnetic structure of Cs0.4 Mn0.4 Fe1.6 F6 and of Cs0.4 Ni0.4 Fe1.5 F6

The magnetic structure of the two compounds as determined by neutron diffraction is reported. Both compounds are antiferromagnetic with Néel-temperatures of 115 and 100 K respectively. Both compounds show a very pronounced diffuse scattering.     

Lithium motion in Li0.33 TiS2 and Li0.94 TiS2

We have studied the motion of lithium ions in Li_xTiS₂ (x = 0.33, 0.94) using pulsed NMR techniques. The temperature dependences of the spin lattice relaxation in the rotating frame (T_1?) suggest comparable activation energies for lithium ion diffusion for both samples, 3370 K, but an appreciably longer hopping time for the x = 0.94 sample. Low temperature values of T₂ agree with calculated and measured second moments for both materials.     

The ν3 and 2ν3 bands of SO3, SO3, SO3, and SO3

This sixth of a series of publications on the high-resolution rotation-vibration spectra of sulfur trioxide reports the results of a systematic study of the ν₃ and 2ν₃ infrared bands of the four symmetric top isotopomers ³²S¹⁶O₃, ³²S¹⁸O₃, ³⁴S¹⁶O₃, and ³⁴S¹⁸O₃. An internal coupling between the l=0(A₁^′) and l=2(E^′) levels of the 2ν₃ states was observed. This small perturbation results in a level crossing between |k−l|=9 and 12, in consequence of which the band origins of the A₁^′,l=0 “ghost” states could be determined to a high degree of accuracy. Ground and upper state rotational constants as well as vibrational anharmonicity constants are reported. The constants for the center-of-mass substituted species ³²S¹⁶O₃ and ³⁴S¹⁶O₃ vary only slightly, as do the constants for the ³²S¹⁸O₃, ³⁴S¹⁸O₃ pair. The S-O bond lengths for the vibrational ground states of the species ³²S¹⁶O₃, ³⁴S¹⁶O₃, ³²S¹⁸O₃, and ³⁴S¹⁸O₃ are, respectively, 141.981 99(1), 141.979 38(6), 141.972 78(8), and 141.969 93(8) pm, where the uncertainties, given in parentheses, are two standard deviations and refer to the last digits of the associated quantity.     

The ν9 + ν11 − ν11, ν10 + ν11 − ν11 hot band system in allene-d4

The hot band system ν₉ + ν₁₁ ? ν₁₁, ν₁₀ + ν₁₁ ? ν₁₁ in allene-d₄ was studied at a resolution near 0.010 cm^?1. About 1500 partly overlapped hot band rotational lines were assigned and fitted to a model taking into account z-Coriolis resonance between the combination levels ν₉ + ν₁₁ and ν₁₀ + ν₁₁ as well as vibrational l-type resonances within these levels. Upperstate constants have been derived from an analysis in which the constants for the ν₁₁ level were constrained. A detailed study of rotational as well as vibrational l-type doublings occurring in the KΔK = ?1 subband is presented, and the sign of vibrational l-type doubling constants for the ν₁₀ + ν₁₁ level is determined. A localized (x, y)-Coriolis resonance between ν₁₀ + ν₁₁ and ν₄(B₁) + ν₁₁ is discussed and the interaction parameter is obtained as well as some constants for ν₄ + ν₁₁.     

Wing profile measurements of the Na-doublet lines in C2H2/O2/N2, H2/O2/N2 and H2/O2/Ar frames at 1 atm

Fluorescence-excitation (wing) profiles of the Na-D doublet lines were measured over a wavelength range extending from 0.3 to 200 Å from the line center for the red D₁ and blue D₂ wings and from 0.3 to 3 Å for the red D₂ and the blue D₁ wings, respectively. The line profiles were determined with the aid of a tunable CW dye-laser as a background source by measuring the total fluorescence intensity observed on detuning the laser wavelength. The flames were premixed, laminar, shielded flames at 1 atm, with temperatures ranging from 1860 to 2270 K; N₂ and Ar served as diluent gases. The line core and near-wing profiles (i.e. the region covering 0.3<Δλ<7 Å for the outer wings and 0.3<Δλ<3 Å for the inner ones) in all of the flames studied appeared to have the same frequency dependence, regardless of the nature and concentrations of the gases used. The blue D₂-line profile followed an unexpected (-2.2) law, while the other three profiles obeyed the theoretically expected (-2) law (the dispersion profile function). The line profile in the Δλ range between the impact and quasistatic regions was found to depend on the main perturbers involved. We found that the far blue D₂- and red D₁-wings in the Ar-diluted H₂/O₂ flame obeyed the (-$\text{5}\text{4}$) and (-$\text{3}\text{2}$) laws, respectively, as predicted by the quasi-static theory for the Lennard-Jones interaction. For the N₂-diluted C₂H₂/O₂ and H₂/O₂ flames, we did not find these wing dependences in the Δλ range investigated.     

Magnetic susceptibility studies of (CH2)3(NH3)2FeCl2Br2 and (CH2)6(NH3)2FeCl2Br2

The magnetic susceptibility of the layered compounds (CH₂)₃(NH₃)₂FeCl₂Br₂ and (CH₂)₆(NH₃)₂FeCl₂Br₂ has been measured in the range 80 < T < 300 K. The results follow a Curie-Weiss behavior in the range 120 < T < 300 K but are field dependent for T < 120 K. The results are interpreted in terms of a two-dimensional antiferromagnetic interaction which is canted. A comparison with the corresponding pure chloride compounds is given.     

The ν2, 2ν2, 3ν2, ν4, and ν2 + ν4 bands of 15NH3

The ir absorption of gaseous ¹⁵NH₃ between 510 and 3040 cm^?1 was recorded with a resolution of 0.06 cm^?1. The ν₂, 2ν₂, 3ν₂, ν₄, and ν₂ + ν₄ bands were measured and analyzed on the basis of the vibration-rotation Hamiltonian developed by V. ?pirko, J. M. R. Stone, and D. Papou?ek (J. Mol. Spectrosc.60, 159–178 (1976)). A set of effective molecular parameters for the ν₂ = 1, 2, 3 states was derived, which reproduced the transition frequencies within the accuracy of the experimental measurements. For ν₄ and ν₂ + ν₄ bands the standard deviation of the calculated spectrum is about four times larger than the measurements accuracy: a similar result was found for ν₄ in ¹⁴NH₃ by ?. Urban et al. (J. Mol. Spectrosc.79, 455–495 (1980)). This result suggests that the present treatment takes into account only the most significant part of the rovibration interaction in the doubly degenerate vibrational states of ammonia.     

Nonplanar domain walls in ferroelastic Gd2(MoO4)3 and Pb3(PO4)2

A new stable, mobile zigzag-shaped domain wall configuration has been discovered in the Gd₂(MoO₄)₃ and Pb₃(PO₄)₂ structures. Previous work on these materials had not predicted this type of domain wall. The zigzag walls have mobilities 30–40 times that of planar walls in the same material. This increased mobility can be explained as a geometrical effect.     

Electron paramagnetic resonance of Mn IN (NH4)2Co2(SO4)3 and (NH4)2Ni2(SO4)3 single crystals

EPR studies are reported on single crystals of ammonium cobalt sulphate and ammonium nickel sulphate containing Mn²⁺ ions. In each case only one magnetic complex of Mn²⁺ ion is found. The resonance lines in the case of Mn²⁺ doped ammonium nickle sulphate are characterised by a strong angular dependence of line intensities. The resonance lines in both the cases are fitted to a spin-Hamiltonian corresponding to orthorhombic symmetry.