Magnetostructural correlations in the cyano-bridged CrNi, Cr2Ni and CrNi6 complexes: density functional theory calculations

Abstract

A theoretical density functional study of the magneto-structural correlations in a series of the cyano-bridged Cr_nNi_m systems is presented. Two approaches with several LDA and GGA functionals gave the result that the ferromagnetic coupling interactions between the nearest-neighbors CrNi weaken with the increase of the number of exchange interactions and the decrease of the Ni–N_brid–C_brid angles. Moreover, Kahn's qualitative theory succeeded in being applied to interpret the relationships J ≈ n (the number of exchange interactions) and J ≈ θ (the Ni–N_brid–C_brid angle) through the overlap integral S_ij and the spin density populations on Cr(III) and Ni(II).