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Vol. 29, No. 8 (1980)

1980-04-20
CONTENT
NONEQUILIBRIUM STATISTICAL FIELD THEORY AND CRITICAL DYNAMICS (Ⅰ)——GENERALIZED LANGEVIN EQUATION
ZHOU GUANG-ZHAO, SU ZHAO-BIN, HAO BAI-LIN, YU LU
1980, 179 (8): 961-968. doi: 10.7498/aps.29.961
Abstract +
Starting from the equations satisfied by the vertex functions on the closed time path, we derived the generalized Langevin equations for the order parameters and the conserved variables. The proper form of the equations for the conserved variables, including automatically the mode coupling terms, was determined from the Ward-Taka-hashi identities and the linear response theory. All existing dynamic models were recovered by assuming the corresponding symmetry properties of the system. The whole theoretical framework is also applicable for describing the systems near steady states far from equilibrium.
NONEQUILIBRIUM STATISTICAL FIELD THEORY AND CRITICAL DYNAMICS (Ⅱ)——LAGRANGIAN FIELD THEORY FORMULATION
ZHOU GUANG-ZHAO, HAO BAI-LIN, YU LU
1980, 179 (8): 969-977. doi: 10.7498/aps.29.969
Abstract +
The expression of the effective action for the order parameters is derived from the continuous integral representation for the generating functional on the closed time path in the one loop approximation for the Fourier transforms. The Lagrangian formulation of the critical dynamics is recovered in the second order approximation of fluctuations in the closed time path continuous integral. The various possibilities of improving the existing theory of critical dynamics are considered.
ENERGY BAND THEORY OF HETEROMETAL SUPERPOSED FILM
ZHANG LI-YUAN, YIN DAO-LE
1980, 179 (8): 978-986. doi: 10.7498/aps.29.978
Abstract +
In this paper, we introduced the concept of the interface plane wave orbits (IPWO). A method for calculating the interface electronic structure of heterometal superposed film was given. It is called MTO-IPWO-PWO Method.
AN EMPIRICAL CORRELATION BETWEEN SUPERCONDUCTING TRANSITION TEMPERATURES Tc AND THE HALL COEFFICIENTS IN AMORPHOUS SUPERCONDUCTORS
LI YU-ZHI, XIA JIAN-SHENG, ZHANG YU-HENG, CAO XIAO-WEN
1980, 179 (8): 987-991. doi: 10.7498/aps.29.987
Abstract +
It is found that there is an empirical correlation between the superconducting transition temperatures Tc and the Hall coefficients RH of amorphous states in numerous non-transition metals and alleys. The same correlation is also exist between the superconducting transition temperatures Tc of amorphous states and the Hall coefficients RHL, of corresponding liquid metals. Prom these empirical correlations we judge that disordered metals, including bismuth thalium zinc, lead and mercury, which have been reported up to now, remain to be not really amorphous.
A.C.CONDUCTANCE OF ORGANIC SOLID THIN FILMS
QIAN REN-YUAN, JIN XIANG-FENG, ZHOU SHU-QIN
1980, 179 (8): 992-999. doi: 10.7498/aps.29.992
Abstract +
The frequency dependence of A.C. conductance of organic solid thin films have been discussed. It is pointed out that the dependence of conductance on the square of frequency is an artifact due to the electrode contact resistance and the capacity of the film. In this paper a method of an added external resistance is proposed to evaluate the electrode contact resistance and thereby the experimentally measured frequency dependences of conductance and capacity of the film could be corrected for the effect of electrode contact resistance. In order to characterize the A.C. conductance of organic solid thin films three parameters are suggested. That is, the D.C. specific conductance σd.c. at extremely low frequencies, the exponent n in the expression σ(f)∝fn for the region of higher frequencies and the value of fx at which the straight line on the lgσ-lgf plot intersects the horizontal line σ=σd.c. For a solution cast film of poly-vinylcarbazole (PVK)-2,4,7-trinitrofluorenone (TNF) (1:0.75) charge transfer complex and an evaporated film of copper phthalocyanine (PcCu) the following results were obtained:PVK-TNF(1:0.75):σd.c.=1.9·10-16(Ω·cm)-1,n=0.96,fx=6.1·10-3Hz at 14℃, PcCu: σd.c.=1.6·10-9(Ω·cm)-1,n=1.2,fx=1·105Hz at 17℃.
A GENERAL TRANSFORMATION FORMULA FOR SHG COEFFI-C1ENTS OF A CRYSTAL AND THOSE OF ITS ANIONIC GROUPINGS
CHEN CHUANG-TIAN, CHEN XIAO-SHEN
1980, 179 (8): 1000-1013. doi: 10.7498/aps.29.1000
Abstract +
By using the irreducible tensor method of representing SHG coefficients, we have proposed in this paper a general transformation formula for SHG coefficients of the macroscopic crystal and those of its microscopic anionic groupings. It thus leads to a series of calculation formulas suitable generally for calculating the contributions of the anionic groupings of different orientations in the crystal to the macroscopic SHG coefficients. It has been shown that this method can be used conveniently to calculate the SHG coefficients of various iodates. The agreements of our calculation values with the experimental ones are quite satisfactory. Our work has provided a dear stero-structural criterion for searching of new types of SHG materials.
MOLECULAR STRUCTURE, CRYSTAL STRUCTURE AND ABSOLUTE CONFIGURATION OF TENACISS IGENIN
TENACISS IGENIN STRUCTURE GROUP
1980, 179 (8): 1014-1022. doi: 10.7498/aps.29.1014
Abstract +
The crystal of Tenaciss igenin with component C21H32O5 belongs to mono-clinic system. The space group is C22—P21. The crystal parameters are as follows: α=10.437?,b=12.467?,c=7.548?,β=109°57′, and of molecules number in an unit cell Z=2. The diffraction data were collected using pw-1100 four-circle diffractometer, the number of independent diffraction data amounts to 1770. The crystal structure was determined by direct method. Refinement of structure parameters was acheived by least-squares method, R= 0.098.The tenaciss igenin is steroid. B-ring and C-ring, C-ring and D-ring all exhibit cisforms. Between the molecules there exist bi-orientation hydrogen-bonds.
A NEW TYPE OF CONTINUOUS SOLID SOLUTIONS ——THE VARIATION OF CRYSTAL STRUCTURE TYPES OF Mgx/2Li1-xIO3 WITH COMPOSITION
LIANG JING-KUI, ZHANG YU-LING, LIU HONG-BIN
1980, 179 (8): 1023-1032. doi: 10.7498/aps.29.1023
Abstract +
The variation of crystal structure types of Mgx/2Li1-xIO3 with composition and temperature has been investigated by the methods of DTA and X-ray powder diffraction both at high and room temperatures. A new type of continuous solid solutions has been found in the entire region of the binary system Mg(IIO3)2·LiIO3.For the solid solutions rich in LilO3, the crystal lattice is distorted in the x-y plane with the increasing concentration of Mg(IO3)2, While the space group changes from P63 to P1121. At the composition 3Mg(IO3)2·7LiIO3, the lattice distortion reaches a maximum,γ=120o22′. With further increasing of the concentration of Mg(IO3)2, the lattice distortion is reduced, and at the composition Mg(IO3)2·LiIO3) the space group turns back again to P63.For the solid solution rich in Mg(IO3)2, the lattice is distorted along the z axis, and has been found to be made of unit cells of heterogeneous parameters c (the effect is most prominent at the composition about 20-30mol% LiIO3). But with increasing temperature, the crystal lattice gradually changes back to unit cells with a uniform parameter.It seems probable that the lattice distortions in the solid solutions are caused by vacancies. The heterogeneous distribution of vacancies results in inhomogeneous parameters c, and it is also due to the presence of vacancies that alters the crystal fields around the anion group, causing the displacement and rotation of IO3- with the result that the lattice is distorted along x-y plane.
THE GEOMETRY OF LATTICE PLANES
YANG QI-BING, YE HENG-QIANG
1980, 179 (8): 1033-1038. doi: 10.7498/aps.29.1033
Abstract +
An analytical method to find correspondence matrix for basic vector transformation is given by using elementary theory of numbers. Methods for drawing of a lattice plane and of a composite lattice plane of two place lattices as well as their applications are discussed.
BANDS OF SCATTERED LIGHT PRODUCED IN AN α- LiIO3 SINGLE CRYSTAL UNDER THE ACTION OF A DC ELECTRIC FIELD
YANG HUA-GUANG
1980, 179 (8): 1039-1047. doi: 10.7498/aps.29.1039
Abstract +
When a laser beam passes through an α-LilO3 single crystal under the action of a DC electric field along the c-axis, it is found that bands of scattered light are produced. The bands are perpendicular to the c-axis and subtend large, angles with the crystal as vertex. The distribution of intensity of the band is not symmetric with respect to the transmitted light spot. When the electric vector of incident beam is perpendicular to the c-axis, then that of scattered beam would be parallel to the c-axis; and when the former is parallel to the c-axis, then the latter would be perpendicular to the c-axis. If the former is neither perpendicular nor parallel to the c-axis then two bands would appear, the electric vectors of which are parallel and perpendicular to the c-axis respectively. Under specific condition, these bands coincide. The polarization, intensity and relaxation behaviour of these bands have been studied in detail. We believe that these bands result very likely from some effect of carriers moving along the c-axis in the crystal. In addition we have observed the defects in the crystal under the action of a DC electric field with optical microscope.
CALCULATIONS OF THE EQUATIONS OF STATE FOR SOME SIMPLE METALS WITH PSEUDOPOTENTIAL METHOD
LI SHU-SHAN, LIN GUANG-HAI
1980, 179 (8): 1048-1057. doi: 10.7498/aps.29.1048
Abstract +
A new method for the determination of the parameter in the pseudopotential of the simplified Heine-Abarenkov model is proposed. In the present method the values of the parameter γc in the pseudopotential and the correction coefficient H for the average value of electron-ion interaction energy are determined from the experimental data of the bulk modulus and the lattice constant of the crystal at 0 K and 0 kbar. The equations of state for eleven simple metals (Li, Na, K, Rb, Cs, Ca, Al, Mg, Zn, Si and Ge) are calculated by means of this model potential and the second order perturbation theory. The calculated pressure-volume relations at 293K are compared with the experimental data. The agreement for all metals is fairly good except Zn for which the discrepancy between the different experimental data is relatively large.
BRIEF REPORT
A NEW METHOD FOR SOLVING THE FREE-BOUNDARG MAGNETIC SURFACE EQUATION WITHOUT CONDUCTING SHELLS
QING CHENG-RUI, SHEN JIE-WU, ZHOU YU-MEI
1980, 179 (8): 1058-1062. doi: 10.7498/aps.29.1058
Abstract +
The iteration method for solving the free-boundary magnetic surface equation with conducting shells has been generalized to the case of infinite region with external currents and without conducting shells. In order to do this a coordinate transformation of the form x′=x/(1+x) is carried out which enables to get a sufficient accuracy inthe region of plasmas while the meshes in the region of vacuum would not be increased. After restricting the radial region of the plasma currents the iteraction series described in [1] can be used to find the equilibrium solution of magnetic surface equation. The numerical solution of this equation in one dimension is obtained and compared with the result obtained analytically. The method described above can effectively be used in cases of two-dimension without difficulties.
HIGH PRESSURE EQUATION OF STATE AND PHASE TRANSFORMATION OF LilO3
XU JI-AN, WANG YAN-YUN, XU MIN-HUA
1980, 179 (8): 1063-1067. doi: 10.7498/aps.29.1063
Abstract +
The equation of state of α and β-LiIO3 is measured by the piston-cylinder technique, we find that the pressed β-LiIO3 can transform to α-phase after stay for an enough long time in the air.
INVESTIGATION OF THE SOLID SOLUTIONS IN ALKALI- METAL IODATE PSEUDO-BINARY SYSTEMS
TANG DI-SHENG, CHE GUANG-CAN, TIAN JING-HUA
1980, 179 (8): 1068-1074. doi: 10.7498/aps.29.1068
Abstract +
Among the 21 pseudo-binary systems formed by alkali-metal iodates (including HIO3 and NH4IO3), there are 9 in which compounds can be synthesized in aqueous solutions or by powder-sintering, 6 which are mixtures of the constituents; and the rest of the systems can formed continuous solid solutions. The pseudo-binary systems KIO3-NHJO3, RbIO3 etc. were studied by means of thermal analysis (DTA, TG) and Xray diffraction, and were found to be of continuous solid solutions. With addtion of KIO3 or RbIO3, the phase transition temperature of NH4IO3 is decreased and its decomposition (at the same time burning) temperature is raised; the room temperature phase of NH4IO3 (monoclinic) is transformed gradually into cubic phase with increasing content of KIO3 or RbIO3. Samples in the binary systems with NH4IO3 as a component exhibit good pyroelectric property. In this paper, the stability and the change of lattice parameter with compositions of the solid solutions that were found in alkalimetal iodate binary systems were also discussed.
CRYSTAL GROWTH, MORPHOLOGY AND OPTICAL PROPERTY OF COMPLEX SALT KIO3 2LiIO3
HU BO-QING, MA WEN-YI, ZHOU TANG
1980, 179 (8): 1075-1079. doi: 10.7498/aps.29.1075
Abstract +
The growth condition of the complex crystal KIO3·LiIO3 and its infrared spectra have been investigated. The morphology of the crystal has been determined. Its class is 2/m. The parameters of its cell are a = 11.189, b = 11.038, c = 8.262, β = 111°27′. The position of the optical indicatoid for the crystal, the refraction indices in the range of visible light and their Sellmeier's equations have been given.
CRITERION OF PRIMITIVE SOLUTIONS IN THE AUTOMATIC INDEXING OF ELECTRON DIFFRACTION PATTERNS
GOU KE-XIN, LIU PING
1980, 179 (8): 1080-1083. doi: 10.7498/aps.29.1080
Abstract +
Electron diffraction patterns can be automatically indexed by comparing two nearest diffraction spots with two calculated reciprocal vectors r1* and r2*2, r1*×r2*= Au. However, non-primitive solutions corresponding to non-primitive reciprocal plane cells, sometimes result. For simple Bravais lattices, obviously A=1 is the criterion of primitive solutions. For primitive solutions in centred Bravais lattices, it has been shown that A has also specified values for various combinations of u, v, w indices.
QUANTUM MECHANICAL TREATMENT OF A DAMPED HARMONIC OSCILLATOR
PENG HUAN-WU
1980, 179 (8): 1084-1089. doi: 10.7498/aps.29.1084
Abstract +
Assuming a damping force proportional to the velocity, it is shown that the usual quantum condition between the physical variables, namely the displacement and the momentum, has to be modified by the damping. However, it is possible to change to new variables which are canonical. Then we can apply the usual quantum mechanics and use the usual physical interpretation through the statistical average values. The case of a one-dimensional damped harmonic oscillator under the action of an arbitrary external force has been worked out as an example. No difficulty arises and the results are reasonable.
FURTHER TEST FOR THE "AN EMPIRICAL RULE FOR SUPERCONDUCTING A-15 TYPE COMPOUNDS"
LUO QI-GUANG
1980, 179 (8): 1090-1092. doi: 10.7498/aps.29.1090
Abstract +
The author discusses recent experimental results which agree well with predictions given by his previous paper.