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).
De Fusco, G.C., Pisani, L., Montanari, B., Harrison, N.M. (2009). Density functional study of the magnetic coupling in V(TCNE)2. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 79(8), 1-8 [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.