Deuterium Nuclear Quadrupole Interaction in FC≡CD, CH3C≡CD, and ClC≡CD

Abstract

The deuterium nuclear quadrupole coupling constants of CH3–C≡C–D, Cl–C≡C–D, and F–C≡C–D have been determined in order to investigate the effect of substitution on the electron distribution in the C—D bond. The results along the C—D bond yield χD=208±10 kc/sec for CH3–C≡C–D, χD=212±10 kc/sec for F–C≡C–D, and χD=225±18 kc/sec for Cl–C≡C–D. The results show equal deuteron field gradients within experimental error and therefore show that the C—D bond is relatively insensitive to the substitution at the other end of the acetylenic bond.