Theoretical study of the magnetic properties of bis(ethylenediseleno)tetrathiafulvalene (BEST) with the octahedral anions hexacyanoferrate(III) and nitroprusside

First-principles calculations have been performed to study the electronic band structure and its magnetic property for the compound of bis(ethylenediselena)-tetrathiafulvalene(BEST) with the paramagnetic hexacyanoferrate(III) [Fe(CN)6]3− or the photochromic nitroprusside anion [Fe(CN)5NO]2−. From the total and partial density of states and atomic spin magnetic moments, it is found that the spin magnetic moments of (BEST)4[Fe(CN)6] is mainly assembled at the iron atom and the cyanogen radical and the spontaneous magnetic moments for (BEST)2[Fe(CN)5NO] come from iron atom, cyanogen and nitric oxide radical. In particular, there exist small magnetic moments at Se and S atoms and there formed the alternating +/−/+ spin population of C/Se/S, which means there exists antiferromagnetic exchange interaction in the organic layers.