Anisotropic covalency effect

The effects of anisotropic covalency on the quadrupole splitting of high-spin ferric compounds has been considered theoretically for compounds of... 

Although these effects are small, they affect not only the covalent X-H bond lengths, but also the H - A hydrogen-bond lengths. For very high-precision low-temperature neutron diffraction analyses [186, 187], they have to be taken into account. An adequate way to do this, without the complexity of a complete anhar-monic thermal motion analysis, is to use the experimentally determined anisotropic temperature factors. As shown by comparisons between experimental and theoretical X-H values from low temperature neutron analyses and theoretical ab-initio molecular orbital calculations, one can assume that the motion of the two... 

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