Neutron powder diffraction on α-Tl4CrI6 and β-Tl4CrI6 |
| |
Authors: | HW Zandbergen |
| |
Institution: | Gorlaeus Laboratories, University of Leiden, P.O. Box 9502, 2300 RA Leiden, The Netherlands |
| |
Abstract: | α-Tl4CrI6 (a = 9.132(1), c = 9.667(1) Å, at 293 K) adopts a distorted Tl4HgBr6 structure. In α-Tl4CrI6 there occurs a random distribution of Jahn-Teller distorted octahedra which are elongated perpendicular to the c axis. Between 77 and 4.2 K a phase transition occurs. In β-Tl4CrI6 (a = 12.941(3), b = 12.596(3), c = 9.602(2) Å, Z = 4, Cccm at 4.2 K) the directions of elongation of the octahedra are ordered. The structure is very much related to that of α-Tl4CrI6. A three-dimensional magnetic ordering takes place at 2.7(2) K. The magnetic space group at 1.2 K is CI22′2′. The magnetic moments (3.48(6) μB) are parallel to (0 0 1) and have an angle of 41(9)° with the a axis. Four magnetic sublattices are present, forming two independent magnetic lattices which have no interaction due to the antiparallel ordering. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|