Eur. Phys. J. B 51, 173-180 (2006)
https://doi.org/10.1140/epjb/e2006-00207-9

Magnetic properties and ¹¹⁹Sn hyperfine interaction parameters of LiMn₆Sn₆

Laboratoire de Chimie du Solide Minéral, Université Henri Poincaré-Nancy I, Associé au CNRS (UMR 7555), B.P. 239, 54506 Vandoeuvre-lès-Nancy Cedex, France

Corresponding author: ^a thomas.mazet@lcsm.uhp-nancy.fr

Received: 15 February 2006
Revised: 27 March 2006
Published online: 1 June 2006

Abstract

We have synthesized LiMn₆Sn₆, the first RMn₆Sn₆ compound involving an alkali metal as R element. It crystallizes in the hexagonal (P6/mmm) HfFe₆Ge₆-type structure. From magnetic measurements and powder neutron diffraction experiments it is found that LiMn₆Sn₆ magnetically orders at T_C = 380 K in a simple easy-plane ferromagnetic structure (m_Mn = 2.58 μ_B at 2 K). The ¹¹⁹Sn Mössbauer spectrum recorded at 5 K indicates that the tin nuclei experience huge hyperfine fields (as large as 35 T). Electronic structure calculations are used to gain information about the microscopic origin of both the hyperfine field and electric field gradient at the Sn nuclei. The former arises due to spin-dependent hybridization between the 5s states of Sn and the 3d states of Mn. The latter comes from the 5p charge density close to the nucleus, whose anisotropy is mainly produced through directional interactions with the 3d states of the first Mn neighbors. Comparison between experimental quadrupole splittings and theoretical electric field gradients allows us to propose a value of for the quadrupole moment of the first excited state (I= 3/2) of the ¹¹⁹Sn nucleus.