Optical rotation of molecules in beams: the magic angle

Abstract

Abstract Measurements of optical rotation of molecules in beams should now be possible with ultra-sensitive polarimeters, and would open the door to many interesting new experiments, including determination of the optical rotation of individual rotational states. The “magic angle” is used widely in magnetic resonance, and in this paper, we introduce it for the first time to optical rotation studies. We show that although the optical rotation is in general different for different rotational states, these differences disappear if the polarimeter's light beam is applied at the “magic angle” to the externally applied electric field used to separate the states.