A critical assessment of the use of compliance constants as bond strength descriptors for weak interatomic interactions

Inverse compliance constants (inverse diagonal elements of the inverse Hessian matrix) have frequently been proposed as replacements for regular internal coordinate force constants, as the former are invariant to the choice of internal coordinates while the latter are not. Recently, Grunenberg and co-workers have proposed using compliance constants as descriptors of bond strength, primarily based on their invariance properties. This article critically assesses the use of compliance constants as bond strength descriptors, highlighting reasons why their use for this purpose is considered inappropriate, particularly for weak bonding interactions. (c) 2006 American Institute of Physics.