Isotope Effects on Dipole Moments, Polarizability, NMR Shielding, and Molar Volume

Isotope Effects on Dipole Moments, Polarizability, NMR Shielding, and Molar Volume 

Abstract Although the electronic structure and the electrical properties of molecules in first approximation are independent of isotope substitution, small differences do exist. These are usually due to the isotopic differences which occur on vibrational averaging. Vibrational amplitude effects are important when considering isotope effects on dipole moments, polarizability, NMR chemical shifts, molar volumes, and fine structure in electron spin resonance, all properties which must be averaged over vibrational motion. 

In this way one obtains the mean value of P averaged over vibrational motion in terms of mean displacements, mean square displacements, and so on. This approach has been long used to discuss isotope effects on electrical properties of molecules. 

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