MOLECULAR-STRUCTURE AND INTERNAL-ROTATION OF (Z)-CHLOROACETALDEHYDE OXIME BY GAS-PHASE ELECTRON-DIFFRACTION

The molecular structure of gaseous (Z)-chloroacetaldehyde oxime has be en determined by gas-phase electron diffraction and molecular structur e optimization has been carried out by molecular orbital calculations. The molecular skeleton is planar and the potential barrier height to internal rotation around the C-C bond (V1) was estimated to be 2.7 kca l mol-1. The geometrical parameters obtained are: r(g)(C-Cl) = 1.789 /- 0.001 angstrom, r(g)(C-C) = 1.513 +/- 0.003 angstrom, r(g)(C=N) = 1 .284 +/- 0.001 angstrom, r(g)(N-0) = 1.416 +/- 0.001 angstrom, angle C CCl = 109.7 +/- 0.2-degrees, angle CCN = 124.9 +/- 0.3-degrees, angle CNO = 110.6 +/- 0.2-degrees.