Journal of Research (Science)
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STUDY OF THE EFFECT OF ATMOSPHERE AND WATER VAPOR ON THIN DEPOSITS OF ALKALI HALIDES ON CARBON
Department of Physics, Islamia University, Bahawalpur, Pakistan.
Abstract: Thin continuous carbon film for use as substrate has been prepared by using a new technique. Thin layers of CsBr, CsI, CsF and LiF on carbon substrate from the vapor phase has been deposited, exposed to atmosphere or water vapor and then studied by transmission electron microscope. Thin layers of alkali halides absorb water to make tiny droplets of their solution. The water evaporates in the electron microscope leaving behind a number of oriented small crystals or a quite large single crystal depending upon the thickness of unexposed deposit and time of exposure. The perfection and the shape of the crystals depend on the rate of crystallization.
Keywords:Alkali halides, carbon film, crystallization, exposure to atmosphere, exposure to water vapor, unexposed deposit, vacuum evaporation.