  We use correlation potential and many-body perturbation theory techniques to
calculate spin-independent and nuclear spin-dependent parts of the parity
nonconserving amplitudes of the transitions between the $6s_{1/2}$ ground state
and the $5d_{3/2}$ excited state of Ba$^+$ and Yb$^+$ and between the
$7s_{1/2}$ ground state and the $6d_{3/2}$ excited state of Ra$^+$. The results
are presented in a form convenient for extracting of the constants of
nuclear-spin-dependent interaction (such as, e.g., anapole moment) from the
measurements.
