How polarizabilities and C6 coefficients actually vary with atomic volume

In this work, we investigate how atomic C 6 coefficients and static dipole polarizabilities α scale with effective volume. We show, using confined atoms covering rows 1-5 of the periodic table, that and (for volume ), where , α^R, and V^R are the reference values and effective volume of the free atom. The scaling exponents pZ and vary substantially as a function of element number Z = N, in contrast to the standard "rule of thumb" that pZ = 2 and . Remarkably, we find that the polarizability and C 6 exponents p′ and p are related by p′ ≈ p − 0.615 rather than the expected p′ ≈ p/2. Results are largely independent of the form of the confining potential (harmonic, cubic, and quartic potentials are considered) and kernel approximation, justifying this analysis.

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