Single-crystal structures and electron density distributions of ethane, ethylene and acetylene. III. Single-crystal X-ray structure determination of ethylene at 85 K

Abstract

Crystalline C2H 4 at 85 K is monoclinic, a = 4.626 (1), b = 6.620 (2), c = 4.067 (2)/k, fl = 94.39 (2) °, space group P21/n, Z = 2. The intensities of all reflexions with sin 0/X < 1.07/t,-~ were measured at two ~, values on a Nonius four-circle diffractometer. A valence analysis with multipole deformation terms up to octopole on C and up to quadrupole on H has been performed by anisotropic least-squares refinement on/, including extinction, on the 1295 independent reflexion intensities. Both ~ and SCF scattering factors were