The variation of the Curie constant with dilution of the chromium ion in potassium chromium alum at helium temperatures

Abstract

In this dissertation we report the variation of the Curie constant with dilution of the chromium ion in potassium chromium alum at temperatures between 1.1°K. and 4.2° K. We grew several samples of mixed crystals of potassium chrome alum with potassium aluminum alum, each vrith a different concentration of the chromium ion. Samples of undiluted potassium chromium alum and pure potassium aluminum alum were grown also. The magnetic susceptibilities of the samples were measured at temperatures in the helium range. The percentage of chromium ions in each sample was determined by density comparison. We found that each sample followed the Curie law very closely and thus each Curie constant was well defined. The Curie constant for each sample was directly proportional to the quantity of the chromium ion contained. This linear relationship precludes the possibility of interaction between the paramagnetic ions since a magnetic interaction would involve a curve of higher order.