MAGNETIC ROTATION OF DIAMAGNETIC OXIDE CRYSTALS AND THE ORIGIN OF DIAMAGNETIC ANISOTROPIES

A new type of field-induced oscillation is reported for synthetic and natural inorganic crystals. This oscillation occurred when the restori ng force of the suspending string was negligible compared to the diama gnetic anisotropy energy in the high field region. The period of oscil lation, tau, was proportional to the reciprocal of the field intensity , H, as, tau = 2 pi root I/(2N Delta(X))(1/H). The value of diamagneti c anisotropy, AX, was estimated, with the sensitivity being improved t o 2 x 10(-11) emu/cm(3) for a single crystal of about 100 cm(3). A new mechanism was proposed for the diamagnetic anisotropy, in which the o rigin of Delta(X) is assigned to the anisotropy of the bonding electro ns. The new method of Delta(X) measurement is effective to compile unk nown Delta(X) data of various diamagnetic oxides with small Delta(X) v alues, in the course of evaluating the anisotropy model quantitatively .