The Journal of Physical Chemistry A

Slowing and Speeding Molecular Beams by Means of a Rapidly Rotating Source

Manish Gupta, Dudley R. Herschbach

Published Jan 3, 2001• 113 citations

Abstract

Mounting a molecular beam source near the tip of a hollow high-speed rotor provides a means to shift the velocity distribution of the beam downward or upward over a wide range. We describe the construction of such a device and experiments and model calculations characterizing its operation, for both supersonic and effusive beams of rare gases, O 2, CH 3 F, and SF 6 . For example, the flow velocity of a rotating supersonic beam of O 2 was accelerated to above 1000 m/s (corresponding to a kinetic energy of 2200 K and deBroglie wavelength of 0.1 Å) and decelerated (when seeded in Xe) to below 70 m/s (corresponding to a kinetic energy below 10 K and deBroglie wavelength of nearly 2 Å). With improvements in prospect, the rotating beam source offers a versatile and relatively simple way to enhance techniques for manipulating molecular trajectories.

DOI: 10.1021/jp002640u

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