  Nuclear-spin-dependent (NSD) parity violating (PV) effects can be strongly
enhanced in diatomic molecules containing heavy atoms. Future measurements are
anticipated to provide nuclear anapole moments and strength constants for PV
nuclear forces. In light molecules, the NSD electroweak electron-nucleus
interaction may also be detected. Here we calculate NSD PV effects for
molecular ions. Our calculations are motivated by rapid developments in
trapping techniques for such systems at low temperatures.
