A simple model structure of the room-temperature magnetic semiconductor V(TCNE)(2) is proposed on the basis of available experimental data. The structural, electronic, and magnetic properties are investigated using hybrid-exchange density functional theory within periodic boundary conditions. A spin-polarized ferrimagnetic ground state with a total spin of 1 mu(B) per formula unit is identified. The analysis of the corresponding electronic band structure and spin distribution reveals strong interactions between the V ions and the [TCNE](center dot-) radicals, identified as spin carrying units. Within a simple Ising Hamiltonian, a strong antiferromagnetic coupling between the metal and its nearest-neighbor ligands is predicted which is consistent with the observed high-temperature magnetic ordering. The computed results provide useful insight into the physical origin of the exceptional magnetic behavior of V(TCNE)(2).
Density functional study of the magnetic coupling in V(TCNE)2 / De Fusco, Giulia C.; Pisani, Leonardo; Montanari, Barbara; Harrison, Nicholas M.. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - ELETTRONICO. - 79:8(2009), pp. 085201.1-085201.8. [10.1103/PhysRevB.79.085201]
Density functional study of the magnetic coupling in V(TCNE)2
Pisani, Leonardo;
2009
Abstract
A simple model structure of the room-temperature magnetic semiconductor V(TCNE)(2) is proposed on the basis of available experimental data. The structural, electronic, and magnetic properties are investigated using hybrid-exchange density functional theory within periodic boundary conditions. A spin-polarized ferrimagnetic ground state with a total spin of 1 mu(B) per formula unit is identified. The analysis of the corresponding electronic band structure and spin distribution reveals strong interactions between the V ions and the [TCNE](center dot-) radicals, identified as spin carrying units. Within a simple Ising Hamiltonian, a strong antiferromagnetic coupling between the metal and its nearest-neighbor ligands is predicted which is consistent with the observed high-temperature magnetic ordering. The computed results provide useful insight into the physical origin of the exceptional magnetic behavior of V(TCNE)(2).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.