Electron Diffraction by Liquids

Electron interference has been obtained by the transmission of electrons (14 to 30 kv) through thin liquid films of phytol (C₂₀{H}₃₉$OH), Nujol and two different grades of Cenco vacuum pump oil. The patterns obtained for these four liquids are all practically the same and are characterized by three complete diffraction rings. The values of (1λ)sinθ2 for phytol were found to be 0.108, 0.236 and 0.420. These rings could be produced by diffracting planes of spacings 4.63A, 2.1A and 1.2A. These distances are practically identical with the values obtained by G. W. Stewart for x-ray diffraction in liquid pentadecane (C₁₅{H}₃₂$) and tetradecane (${C}₁₄H₃₀). The problem of interpreting the results by a group theory such as proposed by Stewart is the same for electrons as for x-rays.