Nature of magnetic and electronic structure of double perovskite A2FeMoO6

The nature of magnetic and electronic structure in double perovskite structure A2FeMoO6 （A= Sr, a, Ca） was calculated using the local spin density approximation （LSDA） and the LSDA＋U Coulomb interaction method of density functional theory. The result shows that Sr2FeMoO6 is magnetic metallic material, whereas Ba2FeMoO6 and Ca2FeMoO6 are half-metallic materials. Fe has great effect on the magnetic property of double perovskite structure A2FeMoO6 materials. Because of the orbit hybridization and polarization between the metal element and O element, the Mo element has magnetic properties. The static magnetic moment of double perovskite structure A2FeMoO6 materials, the value of the magnetic moment of these A2FeMoO6 for （A=Ca, Sr, Ba） are 3.626 43μB, 2.678 64μB, 3.706 17μB, respectively. The magnetic moment of Fe element in the crystal cell are, 3.626 43μB, 2.678 64 μB, 3.706 17μB. And the energy of crystal cells are -28 540.561 907Ry, -24 268.037 272Ry, -44 106.187 179Ry, These values are in agreement with the experiment values.