Figure 5: Results of first-principles calculations and mechanism of ferromagnetism.
From: Room temperature ferromagnetism in Teflon due to carbon dangling bonds
(a) The energy difference between ferromagnetic and antiferromagnetic states (EFM–EAFM) as a function of C–C distance in the 1D chain of C dangling bonds; (b) The energy difference between ferromagnetic and antiferromagnetic states (EFM–EAFM) as a function of C–C distance in the 2D network of C dangling bonds (solid line) and in the 2D network of C dangling bonds attached with H2O (dashed line); (c) side view and (d) top view of spin density in the 2D network of C dangling bond model of Teflon tape; the spin density is defined as the difference between spin-up and spin-down electron densities. Positive spin density is shown in brown (upper) and negative (lower) ones in blue. Carbon and fluorine atoms are shown using red and blue balls, respectively. (e) Spin-polarized density of states of 2D C dangling bonds; spin-up (upper) is shown in black and spin-down (lower) in red. The Fermi energy is indicated by the vertical dashed line. All results are obtained based on a hybrid functional (PBE0).
