Low-energy excitations and thermodynamical properties of the quantum (5/2, 1/2, 1/2) ferrimagnetic chain
A S Ovchinnikov; I G Bostrem; V E Sinitsyn; A S Boyarchenkov; N V Baranov; K Inoue; A S Ovchinnikov; Department of Physics, Ural State University, Lenin Ave. 51, 620083 Ekaterinburg, Russia; Applied Molecular Science, Institute for Molecular Science, Nishigounaka 38, Myodaiji, Okazaki 444-8585, Japan; I G Bostrem; Department of Physics, Ural State University, Lenin Ave. 51, 620083 Ekaterinburg, Russia; Applied Molecular Science, Institute for Molecular Science, Nishigounaka 38, Myodaiji, Okazaki 444-8585, Japan; V E Sinitsyn; Department of Physics, Ural State University, Lenin Ave. 51, 620083 Ekaterinburg, Russia; Applied Molecular Science, Institute for Molecular Science, Nishigounaka 38, Myodaiji, Okazaki 444-8585, Japan; A S Boyarchenkov; Department of Physics, Ural State University, Lenin Ave. 51, 620083 Ekaterinburg, Russia; Applied Molecular Science, Institute for Molecular Science, Nishigounaka 38, Myodaiji, Okazaki 444-8585, Japan; N V Baranov; Department of Physics, Ural State University, Lenin Ave. 51, 620083 Ekaterinburg, Russia; Applied Molecular Science, Institute for Molecular Science, Nishigounaka 38, Myodaiji, Okazaki 444-8585, Japan; K Inoue; Department of Physics, Ural State University, Lenin Ave. 51, 620083 Ekaterinburg, Russia; Applied Molecular Science, Institute for Molecular Science, Nishigounaka 38, Myodaiji, Okazaki 444-8585, Japan
Журнал:
Journal of Physics: Condensed Matter
Дата:
2002-09-02
Аннотация:
The low-energy structures of the quantum ferrimagnetic Heisenberg chain consisting of (5/2, 1/2, 1/2) trimers are investigated theoretically. The results of the linear spin-wave theory are compared with those from the numerical exact diagonalization calculation and the matrix product method for the lowest optical mode. The temperature behaviour of thermodynamical properties such as magnetic susceptibility, specific heat and entropy are analysed in the framework of the modified spin-wave theory. The results of the calculations are used to explain the experimental data obtained for the molecule-based heterospin magnets [Mn(hfac)<sub>2</sub>BNO<sub>R</sub> ] (R H, F, Cl, Br) with one-dimensional chain structure.
191.8Кб