The Crystal Structure of Methylene Bichloride, CH2Cl2

The crystal structure of methylene dichloride has been determined by the X-ray diffraction method at about −120°C. The structure has a symmetry D2h14–Pbcn, and its orthorhombic tetramolecular cell has these dimensions: a=4.249±0.001, b=8.138±0.020, and c=9.492±0.002 A. The positional parameters of the chlorine and carbon atoms are obtained by a three-dimensional Patterson function, followed by a least-squares refinement including the hydrogen atom. The structure thus obtained is in excellent agreement with the results of lattice-energy calculations. The crystal structure is quite different from that of methylene dibromide (and of methylene diiodide).