PENDULAR ALIGNMENT OF PARAMAGNETIC MOLECULES IN UNIFORM MAGNETIC-FIELDS

For paramagnetic molecules subjected to a uniform magnetic field, the Zeeman interaction produces widely tunable, aligned pendular states in which the molecular magnetic dipole librates about the field direction. We demonstrate such alignment by observing spectroscopic transitions at almost-equal-to 1 T involving the A 3PI1 excited state of ICl, and extract characteristic pendular eigenproperties that arise from the hybridization of field-free rotor states. Unlike the electric analog, magnetic pendular states can be created for nonpolar molecules and molecular ions.