An atomic distribution curve for a simple monatomic liquid, such as argon, is generally characterized by a prominent first peak. This peak may be used to determine the elements of the first coordination shell, i.e., the radius of the shell and the number of nearest neighbors of an atom. Frequently this peak can be closely approximated by a simple polynomial involving a parameter $\sigma$. This parameter may be determined empirically by a process of fitting. In the case of liquid argon, where the force function between the atoms is known, it is possible to make a theoretical determination of $\sigma$ provided the elements of the first coordination shell are given. This has been done for liquid argon at a temperature of 91.8°K and under a pressure of 1.8 atmos. The theoretical value of $\sigma$ is compared with various empirical values obtained from the experimental distribution curve for liquid argon under these conditions as given by Eisenstein and Gingrich. It is found that the theoretical value is somewhat smaller than the empirical value of $\sigma$ obtained by fitting and slightly larger than that obtained by the Coulson-Rushbrooke method. A possible interpretation of these results is given.

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