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Calculation of the static electronic second hyperpolarizability or chi(3) tensor of three-dimensional periodic
Roberto Orlando1, Mauro Ferrero, Michel Rérat
1Dipartimento di Scienze e Tecnologie Avanzate, Universita del Piemonte Orientale, Viale T. Michel 11, 15121 Alessandria, Italy. roberto.orlando@unito.it
Abstract:
The coupled perturbed Hartree-Fock (CPHF) method for evaluating static first (beta) and second (gamma) hyperpolarizability tensors of periodic systems has recently been implemented in the CRYSTAL code [Bishop et al., J. Chem. Phys. 114, 7633 (2001)]. We develop here an efficient and accurate computational protocol, along with the local basis sets needed for first and second row atoms. Application is made to several high symmetry three-dimensional systems including one (pyrope) with an 80 atom unit cell. CPHF second-order hyperpolarizabilities substantially undershoot experimental values, due to an overestimate of the band gap, but trends are satisfactorily reproduced for beta as well as gamma.
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