Long-range magnetic order in quasi-one-dimensional chromium-based, S=3/2 pyroxenes, (Li,Na)Cr (Si,Ge)(2)O-6

作者：Vasiliev AN^*; Ignatchik OL; Sokolov AN; Hiroi Z; Isobe M; Ueda Y

来源：Physical Review B, 2005, 72(1): 012412.

DOI：10.1103/PhysRevB.72.012412

Quasi-one-dimensional Cr-based (d(3), S= 3/2) pyroxenes (Li, Na) Cr (Si,Ge) O-2(6) reach long-range magnetic order at low temperatures. At substitution of small size cations Li1+ and Si4+ for large size cations Na1+ and Ge4+ the competition between antiferromagnetic and ferromagnetic exchange interactions strengthens so that antiferromagnetic long- range order in LiCrSi2O6 (T-N= 11 K), LiCrGe2O6 (T-N= 3.7 K), and NaCrSi2O6 (T-N = 3 K) changes for ferromagnetic long- range order in NaCrGe2O6 (T-C= 6 K). This tendency is tentatively attributed to diminishing direct overlap of Cr t(2g) orbitals responsible for antiferromagnetic exchange interaction against background of ferromagnetic Cr-O-Cr superexchange interaction.

• 出版日期2005-7