The static dipole polarizability of C70 fullerene

The electronic and vibrational contributions to the static dipole polarizability of C-70 fullerene are determined using the finite-field method within the density functional formalism. Large polarized Gaussian basis sets augmented with diffuse functions are used and the exchange-correlation effects are described within the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA). The calculated polarizability (alpha) of C-70 is 103 angstrom(3), in excellent agreement with the experimental value of 102 angstrom(3) and is completely determined by the electronic part, the vibrational contribution being negligible. The ratio alpha(C-70)/alpha(C-60) is 1.26. The comparison of polarizability calculated with only local terms (LDA) in the PBE functional to that obtained with PBE-GGA shows that LDA is sufficient to determine the static dipole polarizability of C-70.