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Halocarbons 1: Methane Derivatives



Arno D. Laesecke


This poster (47 in x 30 in) shows ab initio computed structures of the chlorine and/or fluorine derivatives of methane. Some of these compounds are working fluids (ozone depleting and alternative) in refrigeration and air conditioning equipment. Others are used as precursors in syntheses, as solvents, and in medical applications like anesthesia, blood substitutes, and preservation. The molecules are rendered in terms of two isoelectron density surfaces and their associated electrostatic potentials. This visualization gives not only an impression of molecular size and shape, but also of the charge distribution in these mostly quite polar compounds. This is a considerably more detailed view of molecular structure than conventional ball-and-stick or space-filled models. The poster includes a brief text entitled Our Evolving View of Molecular Structure which explains the molecular structures and the underlying computational chemistry methods.
Special Publication (NIST SP) - 954
Report Number


ab initio calculations, computational chemistry, electron density distribution, electrostatic potential, halocarbons, molecular structure, refrigerants, visualization


Laesecke, A. (2000), Halocarbons 1: Methane Derivatives, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 14, 2024)
Created October 1, 2000, Updated November 10, 2018