Gas-phase electron diffraction reveals an average linear central backbone in hexamethylcarbodiphosphorane, suggesting apparent bending stems from low-frequency vibrational shrinkage.
The molecular structure of hexamethylcarbodiphosphorane, (CH3)3PCP(CH3)3, in the gas phase has been determined by electron diffraction. Principle bond lengths (ra) are: PC, 181.4(3) pm, PC, 159.4(3) pm; CH, 108.9(4) pm. The angles between the PC (methyl) bonds are 101.4(3)°, and the apparent PCP angle is 147.6(5)°. The single structure that fits the experimental data closest has C2 overall symmetry, but an even closer fit is obtained if free rotation about the PC bonds is assumed. This and other evidence indicates that the molecule is probably a symmetric top, and that the PCP unit is linear in the average structure, with shrinkage caused by a low frequency bending vibration giving rise to the apparent non‐linearity.
No takes yet. Share an insight, caveat, or question.
Ebsworth et al. (1977) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: