Temperaturabhängigkeit von Knight-shift und Suszeptibilität von Vanadium und Niob

Knight-shiftK and susceptibility have been investigated on single-crystals of vanadium and niobium between 4 K and 290 K.In the case ofV the changes ofK and are found to be of opposite sign and proportional toT ² with good approximation. This can be explained by theT-dependence of spin-paramagnetism of 3d-electrons. The hyperfine field due to oned-electron spin is found to be — 90 kG. Small deviations from theT ²-law are explained by minor changes in the orbital susceptibility, which gives the main constituents toK and. In the case of Nb only is found to be proportional toT ². TheT-dependence ofK is very small and shows a maximum at 140 K. This can be explained by theT-dependence of spinparamagnetism of 4d-electrons as well as 5s-electrons.     

Bitter-Streifen und Bloch-Wände

Through simultaneous use of the magneto-optic and powder-pattern methods, observations leading to a number of unexpected results were made on the magnetic domains of transformer steel. For example, the colloid lines on the so called stress pattern appear to be located not on the edges of the domains as previously supposed, but in the centers. Through analysis of this and other observations, one must infer that Bitter patterns are not caused by the stray fields of Bloch walls as is usually assumed but predominantly rather by magnetic surface charges on the domains.