Vol. 18, No. 3 (1962)
1962, 83 (3): 117-134. doi: 10.7498/aps.18.117
In this article, the second order perturbation energy for an ion in the crystal field due to all other ions, each being regarded as a point charge, is given as follows Considering this energy in the investigation on the elasticity theory of the alkali halide cry stals by the use of Born and Haung's method, we obtain the deviation of the Cauchy's relation in the following form As an illustration, the numerical values of the deviation are calculated and we conclude that the contribution of the quadrapole term of the second order perturbation energy to the deviation of the Cauchy's relation can not be neglected.
The Lyons-Kaplan method is applied to the discussion of the change of spin configuration of a Bravias lattice in the presence of external magnetic field or magnetic anisotropy. It is shown that the antiferromagnetic structure transforms into ferromagnetic ones above a certain critical field and the formula for this critical field is derived. The stability of the corresponding spin configurations is also examined.
1962, 83 (3): 143-158. doi: 10.7498/aps.18.143
Certain molecules, which are intimately related, have been classified into three types according to the general characteristics with respect to the internal rotation. By symmetry analysis of these three types of molecules the general forms of potential functions have been obtained. Applying the results obtained, and the additive property of interaction energies between chemical bonds, we have calculated the potential functions of 85 molecules. All the calculated results agree well with the experimental data. Besides, the number of isomers of internal rotation and the stable configurations in relation to both the meso and the active forms of two molecules CC1FH-CC1FH and C(CH3)C1H-C(CH3)C1H have been predicted .
Based on the comparison of the infrared spectra of polyamide homologues, on the changes in the infrared spectra of deuterated and iodine-treated samples of polycaprolactam, and also on the observations of the infrared dichroism of drawn film, the main absorption bands of polycaprolactam in the region 400 cm-1-1400cm-1, which are rather structure sensitive, have been assigned as follows: 1370 cm-1 band-νC-N; 1265 cm-1 and 1205 cm-1 bands-δN-H+ν(C-N)(Amide Ⅲ); 1170 cm-1 band-νC-N; 730 cm-1 band-γCH2 of (CH2)n when n≥4; 690 cm-1 band-δN-H (out of plane, Amide V); 580 cm-1 band -δN-H (out of plane).
1962, 83 (3): 167-174. doi: 10.7498/aps.18.167
We derived the gyromagnetic permeability of an antiferromagnet. From the Maxwell equations combined with the permeability we solved for the plane wave solution of the electromagnetic oscillations in an antiferromagnetic medium of infinite extension. Both the exchange effect of the medium and the relativistic effect of the wave propagation were included in this treatment. We calculated the dispersion of waves and obtained a rough estimation for their penetration depth in the medium.