Infrared intensities. Acetylene

The conditions under which the assertion that the effective charge ξC in hydrocarbons is equal to n times ξH, where n represents the number of hydrogen atoms bonded to C, is valid are pointed out. Using atomic polar tensors and the Cartesian intensity sum rule it has been demonstrated that the analysis of relative errors involved in the experimental IR intensities of C2H2 and C2D2 molecules is possible. © 1978 American Chemical Society.