Electronic structure and magnetic properties of potassium ozonide KO(3)

The electronic structure and magnetic properties of potassium ozonide, KO(3), have been investigated by means of periodic spin polarized Hartree-Fock and Density Functional Theory based approaches. These calculations show that KO(3) is a strongly ionic compound with paramagnetic O(3)(-) centers. The most reliable results, provided by the B3LYP hybrid approach, suggest that the system behaves as a magnetic insulator with a gap of approximately 3.0 eV, and with the states around the insulating gap arising mainly from the pi orbitals of the O(3)(-) units while the participation of potassium orbitals in the bands around the band gap is practically negligible. The calculations suggest that, because of the pi character of the magnetic orbitals, the magnetic structure for KO(3) has a significant one-dimensional character, with antiferromagnetically coupled chains along the c axis and a much weaker antiferromagnetic coupling between neighboring chains. This behavior is consistent with available experimental susceptibility data.