Work Function of Iron Surfaces Produced by Cleavage in Vacuum

Kelvin measurements of the contact potential difference between iron surfaces prepared by cleavage in high vacuum and freshly flashed tungsten surfaces are reported. From these measurements, the work function of iron could be found since the work function of the tungsten was known. The work function of the cleavage plane of iron was 4.17±{}0.03 electron volts at liquid nitrogen temperature. Evidence indicating that these measurements were made on clean surfaces is presented. The work function which has been determined is believed to be that of the (100) plane of iron.