Deuteriation of an asymmetric short hydrogen bond. X-Ray crystal structure of KF·(CH2CO2D)2

Abstract

Deuteriation of the strong hydrogen bonds of KF·(CH₂CO₂H)₂ shows no isotope effect on the bond lengths. The only significant change is in the bond angle at the fluoride ion which widens to 128.5 from 116°. The i.r. spectrum shows very little change. Since the O–H ⋯ F^– hydrogen bonds are highly asymmetric, these observations challenge previous predictions about the effects of deuteriation on such bonds.