Magnetic Susceptibility of Alkali Metals

The magnetic susceptibility of alkali metals is evaluated by a systematic development of the grand partition function for small magnetic fields. The results are expressed in powers of $r_s$ (the interparticle spacing divided by the Bohr radius) and compared with recent experimental and theoretical results. The evaluation is made to order $r_s^2$, improving the previous calculations. The polarization parameter, which has been used in the previous evaluation of the paramagnetic susceptibility as an adjustable parameter, is not used. Comparison of our results with the recent experiment by Collings is satisfactory.