  In the case of the one-electron Dirac equation with a point nucleus the
Virial Theorem (VT) states that the ratio of the kinetic energy to potential
energy is exactly $-1$, a ratio that can be an independent test of the accuracy
of a computed solution. This paper studies the virial theorem for subshells of
equivalent electrons and their interactions in many-electron atoms. It shows
that some Slater integrals impose conditions on a single subshell but others
impose conditions between subshells. The latter slow the rate of convergence of
the self-consistent field process in which radial functions are updated one at
a time. Several cases are considered.
