Molecular beams surface ionization detector

The essential elements.of the experiment are a) an effusive molecular beam source, b) inhomogeneous deflecting electric polefaces, c) surface ionization detector, capable of translation in order to obtain the deflected beam pattern. 1, 2, are the distance from the source to the front of the polefaces, the length of the polefaces and the distance from the back of the polefaces to the detector, respectively. A general review of deflection methods for determining polarizabilities is given by Miller and Bederson (8). 

Dudley R. Herschbach (1932- ) began a series of molecular beam experiments at Berkeley starting in 1960. He employed two small ovens with slits producing crossed beams of molecules or atoms under very low pressure that collide in a vacuum reaction chamber. The early apparatus was built upon a turntable directing the stream of products toward a surface ionization detector sensitive to alkah metals and their salts. His first successful experiment crossed beams of potassium atoms and CH3I molecules ... 

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