Physics of Magnetism

14 CHAPTER 3. PARAMAGNETISM OF FREE IONS

in Chapter 8). For one has J = 9/2 and g = 8/11 (see Table 2.2.1). Furthermore,
we make use of the following values

and

At room temperature (298 K), one derives for y in Eq. (3.1.11):

Since we now have shown that under the above conditions, it is justified to use only
the first term of the series expansion of for small values of y

From this follows, keeping only the first term,